A Day in the Life of an Animal Nutritionist

If it moos, oinks, bleats, or clucks it probably lives on a farm. And these farm animals eat a variety of different things. So how does a farmer know what to feed each animal? How do they decided what amounts to feed them? Does an animal’s diet change throughout the animal’s life? Just like humans need different types of food, and in different amounts, so do animals.

To help answer these questions I contacted an animal nutritionist. He specializes in animal nutrition and is especially concerned with the dietary needs of livestock animals.

Role of an Animal Nutritionist

Stewart Galloway is a field nutritionist with Hubbard Feeds. He helps farmers, salespeople, and dealers understand and use the right products when feeding their livestock.

Animal nutritionists can help farmers in many ways, and have different career paths open to them. Some animal nutritionists work for a company that creates animal feed. Their work may include working with numbers, collecting and reviewing lots of research data, and developing nutrition profiles for various animals at different stages of their life. Other animal nutritionists may work as an independent consultant where they interact directly with the farmer customers. This type of role offers lots of flexibility and sometimes travel. Stewart visits livestock producers from Kansas to Pennsylvania. Over time, this industry has become 100% specialized which means there are not many general nutritionists.

Stewart says that working with farmers is the best part of his job because he gets to help them solve problems. There are a great number of details that go into creating the perfect recipe for livestock. He uses technology to help people meet four specific goals: increase profit, improve competitive advantage, decrease risk, and make their lives easier.

Day in the Life of an Animal Nutritionist

Each day, Stewart is problem solving for his farmer customers. Stewart says in his job, “you need to be a person who likes working with a variety of people.”

Some of his duties that he might perform each day include:

  • Formulating diets – Just like you use a recipe to make a food dish, it’s important to get the right ingredients, weights, and mix the right amounts for animal feed. Each animal has varied nutritional needs so an animal nutritionist reviews the food labels and measures the right amount of each ingredient for specific animal types. Food labels contain the amounts of calories, fat, protein, sugar, vitamins, and sugars.
  • Teaching in front of groups of farmers and completing dealer training.
  • Writing articles for various communications media such as extension publications, email, and print trade magazines.
  • Developing decision making tools spreadsheets and dashboards for producers.
  • Creating educational webinars that can be viewed by producers across the country.
  • Conducting meetings with farmers to set goals or check in on their farm animals’ progress, and making feed adjustments as needed.

He says it really helps to be proactive and evaluate any feeding plans a livestock owner has in place. “Animals have a perfect opportunity for good health and nutrition because they don’t have the bad eating habits that some humans do,” he said. One great thing about feeding livestock is animal nutritionists can determine scientifically what animals should eat and predict how they should grow. Stewart mentioned that the genetics in animals now are so good, “we can’t get enough nutrition into them to make them grow as fast as they are capable.”

One surprising thing I learned about Stewart’s job is that he spends little time with the animals. He works with a team of specialists who are actually in the barns. This is not just due to COVID, however. For many years the hog industry has been concerned with biosecurity, and not been able to allow many people to visit in and out of the barns. One of the best ways farmers can keep their animals healthy is by practicing good biosecurity procedures. For more information on biosecurity and its importance, view one of our past blog posts on the topic.

What Kind of Education is Needed?

While in school, Stewart decided he liked animals more than plants, so he went to Iowa State University for Agriculture Studies and gained a diverse agriculture background. After obtaining a master’s degree and a PhD, he went to work in the feed industry. While a master’s degree or Ph.D. is not an absolute requirement, it is more common for individuals in this career field to pursue graduate degrees. A graduate degree is usually required to work in research positions or to secure management or other upper-level roles. Many aspiring animal nutritionists pursue graduate veterinary degrees so they can care for animals in all aspects of their health and nutrition.

If you want more information on what different animals eat, check out this blog Fueling the Body. You will learn what different kinds of fuel people and farm animals need to be healthy and productive.

-Melanie

The STEM of Thanksgiving Dinner

When we sit down to dinner this Thursday, many of us will think about the delicious herbs and spices that make the side dishes mouth-wateringly good. We may think about carving the bird at the center of it all – the turkey. However, we may not think about all of the science, technology, engineering, and math that goes into that Thanksgiving dinner. But maybe we should think about it!

Domestic turkey are usually white. White feathers don’t leave marks in the skin which consumers prefer.

The center piece of Thanksgiving is usually the turkey. The poults (baby turkeys) are raised in a barn to provide the optimal environment – temperature, humidity, and biosecurity. The birds grow from roughly 3.2 ounces to as much as 42 pounds. All of this happens in 19-20 weeks (roughly 5 months) and is possible because of proper nutrition and genetics improved through selective breeding practices. As the turkeys mature, they go through a series of eight different feed rations. They start out with a high level of protein to build body structure, bones, and organs. As they get older, the protein levels are decreased and the carbohydrate levels are increased to promote muscle and meat development. Throughout the entire process, the birds are closely tracked with technology and data is collected to help make good decisions. Many different aspects on the farm help in raising the turkeys sustainably. Solar panels help power the barn and make that ideal environment. Even managing the turkey manure can make the farm more sustainable! The manure is a by-product that has nutrient value in growing crops. The soil can be tested and manure can be added to corn and soybean fields to provide the needed nitrogen, phosphorus, and potassium.

Cranberries are produced on low growing vines. The fields are flooded to harvest the berries which float.

Beyond turkey, there is also the iconic cranberry! In fact, one-fifth of the cranberries eaten in the U.S. are eaten on Thanksgiving! Conjure an image in your mind’s eye of growing cranberries and you’ll likely imagine a cranberry bog with berries floating on top of the water. But that isn’t how they grow! Flooding cranberry fields only happens at the end of the growing season to harvest the cranberries because they are buoyant and the berries will float to the surface of the water when mechanically knocked off the vine. This technology seems simple but is highly innovative taking advantage of the natural physics of the berries. The flooded fields also help protect the plants throughout the winter protecting the flower buds for the next year’s harvest.

Sweet potatoes can take 90 to 170 days to mature.

Many Thanksgiving tables will also feature mashed potatoes or sweet potatoes…or both! Though both are called potatoes they aren’t related – taxonomically speaking. Potatoes, like the white Russet variety, are in the nightshade family like tomatoes. Sweet potatoes, most often with orange flesh, are in the morning glory family. Potatoes are the fourth most farmed crop on the planet. There is a lot of science that goes into producing potatoes. Potatoes are asexually propagated. Cross pollination would result in a lot of variations of potatoes. The only way to ensure similarity and uniformity in the potato harvest is to cut potatoes from the previous year and plant those as root stock for the next year’s crop. Farmers protect their crop from diseases like blight and insects like the potato beetle. Sweet potatoes, on the other hand, are planted by slips – or growing vines. The tubers will grow from the nodes of the slips. The plants will develop large, long vines to harvest the sun’s energy. There are different cultivars that lend themselves well to growing in Iowa and other varieties might be found in grocery stores.

Pie pumpkins have thick, orange flesh and are different from the variety grown for jack-o-lanterns.

And what Thanksgiving table is complete without a pumpkin pie! There are many different varieties of pumpkin. A good pie pumpkin is one that has thick flesh (not the jack-o-lantern variety). Pumpkin seeds are planted in June for an October harvest. The vines will flower and the flowers have to be pollinated by insects before they will produce a fruit. Once harvested, the pumpkins can be processed and canned to provide the filling to a delicious pumpkin pie.

While there are a lot of other side dishes that might grace the table this Thursday, these ingredients are unique. Turkey, cranberries, potatoes, sweet potatoes, and pumpkins all originated and were domesticated in the Americas. They have gained fame around the world for being American. There aren’t a lot of foods that we regularly eat that were domesticated in the Americas, but these staples are.

What other dishes do you put on your Thanksgiving table? Leave a comment to let us know!

-Will

Science 101: Seeds

A seed’s sole mission is to produce another plant. Without seeds, most plant species would not continue and our food, fiber, and fuel choices would be very limited.

Seeds are made up of several components that work together to keep the plant embryo inside alive until conditions are right for the seed to germinate and develop into a seedling that will survive.  Let’s take a look at some of the parts of a seed.

Structure and function of seeds Source: lumenlearning.com

Seeds are protected by a seed coat. This coat can be thin and papery or thick and hard. Thick coats help the embryo to survive through challenging conditions, such as extreme weather or even being eaten by an animal.

The embryo is the part of the seed that develops into a plant. It contains the embryonic root (radical), embryonic stem (epicotyl and hypocotyl), and one or two seed leaves (cotyledons).

Plants with one cotyledon, like corn and rice, are called monocots. If they have two cotyledons, like beans and sunflowers, they are called dicots. In dicots, the seed’s cotyledons form the first leaves of the plant. They are appropriately called cotyledon leaves or seed leaves.

The endosperm contains the starch or stored energy for the developing embryo. In monocots, the endosperm is the largest part of the seed and packed around the embryo.

Seeds are encased in fruit. The fruit protects the seed as it develops and aids in the dispersal of mature seeds. Seed shapes and sizes vary greatly from species to species.  Some, like orchid seeds, are as small as a speck of dust. Others are very large. The seeds of a coconut palm can grow up to 18 inches long.

There are many seeds that farmers grow for food, fiber, and other products. Here’s a look at a few products made from seeds.

Food. Of course, many seed crops are grown for food. Beans can be sold fresh, or dried, frozen, or canned for later use. Rice is a staple food around the world. Wheat is ground into flour for bread and pastries. Soybeans, almonds, and other high-protein seeds can be processed into dairy and meat substitutes. These are just a few examples of the many ways that seeds appear in our diet.

Cooking Oil. Almost all products sold as “vegetable oil” are made from soybeans. The seeds like soybeans are crushed and the oil is extracted and then clarified. Other popular cooking oils made from seeds include sunflower oil, canola oil, peanut oil, corn oil, and sesame oil.

Fuel. Ethanol, or grain alcohol, is derived from the fermentation of corn and other seeds with a high sugar content. Biodiesel is made from soybeans and other seeds with a high oil content.

Spices can come from any dried plant part, but many are derived from seeds. A few popular spices from seeds include black pepper, mustard, nutmeg, celery seed, cumin, paprika, and vanilla.

Livestock Feed. Soybeans are the most common protein source in animal feed worldwide. Just over 70% of the soybeans grown in the United States are used for animal feed. Poultry is the number one livestock consumer of soybeans, followed by hogs, dairy, beef, and aquaculture.

 

-Cindy

Note: This is the sixth post in a series about the science and agricultural importance of plant parts. Previous posts explore roots, stems, leaves, flowers, and fruit.

Science 101: Fruit

Fruits are the prized jewels of the plant and food worlds. They are essential for plant reproduction, as they protect the developing seed and aid in the dispersal of mature seed.  Fruits also provide an important and tasty food source for people and animals.

Botanists, farmers, nutritionists, chefs, and the general public often have different definitions of what makes a fruit a fruit, though. This is because botanical classification is determined by structure and function, while culinary classification considers taste.

Culinarily and nutritionally, a fruit is a sweet or sour-tasting plant part. They are generally eaten raw or made into sweet drinks and desserts. Cucumbers and peppers are not considered fruits in the food world, but rhubarb, which is a leaf stem, is.

Botanically, a fruit is the part of the plant that contains seeds. It is formed from the ovary after flowering. It includes traditional fruits (tree fruits and berries), but also seed-containing vegetables (i.e., squash, tomatoes, peppers, eggplant, etc.) and many nuts (i.e., chestnut, hazelnut, and acorns).

If you’re a self-proclaimed plant and science geek like me or just curious to learn more about plant classification, I highly recommend watching this SciShow video. It is four minutes of head-spinning and witty plant anatomy entertainment.

As stated before, fruits serve two important functions in plant reproduction: seed protection and seed dispersal. Fruits provide a physical barrier between the developing seed and the external environment. Their fleshy inside creates a moist environment for the embryo, or immature seed, and prevents it from drying out too soon. Fruits also provide protection from mammals, birds, and insects. Some have thick skin or shells, contain a toxic substance, or are covered with thorns for extra protection from herbivores.

After the seed is mature, a fruit’s purpose changes dramatically. Instead of protecting the seed, its job is to disperse the seed – or transport it to other locations to germinate and grow. How fruits transport seeds vary greatly from species to species.  Some fruits have wings or a parachute-like structure to carry the seeds by air. Coconut nuts float in water and can be transported miles downstream. Fruits of Impatiens and Viola species explode and catapult seeds onto the ground.

Animals play an important role in seed dispersal, and fruits play a key role in how this happens.  Many fruits are eaten by birds and mammals. The animal digests the fruit, but the seeds pass through the digestive tract and are dropped in other locations.  Some animals, like squirrels, bury nuts to save for later. If the squirrel does not return, the seeds germinate. Some fruits, like cockleburs, have hooks that stick to animal fur and are transported to another place.

There are many fruits that farmers grow for food, fiber, and other products. Here’s a look at a few products made from fruit.

Cooking Oil:  Many cooking oils, including avocado oil, coconut oil, and olive oil are made from fruit with high oil content.  Avocado and olive flesh can contain up to 30% oil.

Juice: This is an obvious, but important use of fruit. In its early days, the juice industry primarily relied on salvaged fruit, which was unsuitable for regular sales because it was misshapen, badly colored, or blemished. Advancement in juice processing, canning and bottling technologies, and cold storage led to increased production and demand for juice.  Now, specific cultivars of apples, citrus, and tomatoes are often are grown specifically for juice.

Pectin is a starch found in the cell walls of fruits and vegetables. When cooked with sugar and acid, it is a gelling agent used to thicken processed food, including jams, jellies, and gummy candies. Commercial pectin is usually made from citrus rinds.

Feed and Silage:  Fruit crops are not usually grown for animal feed, but significant quantities of substandard fruits, peels, cores, seeds, and other by-products of the fruit processing are fed to animals directly or used to make silage. Silage is a fermented feed made by tightly storing green plant material in a silo, silage bag, or silage pit. In parts of the country where seed corn is grown, farmers purchase truckloads of husks, cobs, and discarded grain leftover from seed corn processing. This material has a high sugar and protein content and is perfect for making silage.

– Cindy

Note: This is the fifth post in a series about the science and agricultural importance of plant parts. Previous posts explore roots, stems, leaves, and flowers.

 

 

 

 

 

 

 

Science 101: Flowers

Flowers are probably the most celebrated plant part. We prize them for their beauty, enjoy their fragrance, and use their likeness to adorn our walls and clothing. Flowers get such attention because they are beautiful, but it’s also important to celebrate the critical role they play in our world. Without flowers, most plants wouldn’t be able to reproduce.

The primary role of flowers is reproduction, and reproduction starts with pollination. Flowers have evolved over millions of years to ensure that tiny grains of pollen are carried from the male flower part to the female flower part. Without this transfer, fertilization does not happen, and seeds are not produced. I encourage you to check out our Science 101: Pollination blog post to learn more about how pollination works.

The four main parts of a flower are the sepals, petals, stamen, and pistil. If a flower has all four of these key parts, it is considered to be a complete flower. If any one of these elements is missing, it is an incomplete flower.

Photo Credit: Michigan State University Extension

The sepals are the first part of the flower to form. They protect the petals and other flower parts as they grow and prevent them from drying out.

Petals draw pollinators to the flower and serve as a place for them to land. They are often brightly colored and showy to attract pollinators. Some have several layers of petals, creating a rounded shape, while others are flat.

The stamen is the male reproductive organ of a flower. Each stamen contains two main parts. The anther is at the top and contains the pollen. The filament is the long skinny part of the stamen that holds the anther up for pollinators or wind to reach.

The pistil is the female reproductive organ of a flower. Pistils are generally shaped like a vase or bowling pin and contain three parts – the stigma, the style, and the ovary. The enlarged bottom of the pistil holds the ovary that produces and contains developing seeds. The style is the tube-like structure that connects the ovary to the stigma at the very top of the pistil. The stigma has a sticky texture to capture pollen transported by wind, insects, or birds.

Floriculture is the aspect of agriculture that focuses on growing flowers for decorative use, both inside and outside. Floriculture crops include annual and perennial garden plants for landscape use, potted flowering plants such as orchids, poinsettias, and Easter lilies, and cut flowers used for flower arrangements, corsages, and more.

There are quite a few other flowers that farmers grow for food, fiber, and other products. Here’s a look at a few products made from flowers.

Artichokes are spiny and tough flowers of the plant that usually grow during the fall. Both the wild forms and the cultivated forms of artichokes are consumed all over the world. People in Mediterranean countries including Egypt, Italy, and Spain are the greatest consumers and producers of artichokes today.

Cauliflower. As the name suggests, the cauliflower is also a flower. It is a cool season crop that thrives in a moist atmosphere. It is available year-round, although especially plentiful in the spring and fall. Cauliflower is a low-calorie vegetable, high in fiber, folacin, potassium, and vitamin C.

Broccoli. The edible portion of the broccoli plant is its unopened flower buds and tender stems. If not harvested, the green buds will open to form small yellow flowers. Broccoli is a cool season crop, closely related to cabbage, cauliflower, and Brussels sprouts. Cool season crops are often planted before the last frost and must mature while the weather is still cool. Hot weather and warm soil cause broccoli to flower too quickly, or bolt. Once the plant begins to bolt, anything harvested will be bitter.

Insecticides. Although most flowers attract insects, some repel them. Pyrethrin, also known as pyrethrum, is a chemical compound produced by certain types of chrysanthemum flowers. It is commonly used in pesticide products that control mosquitos, fleas, flies, moths, ants, and other pests. Some species of marigolds are also used to make nematode repellents.

Fragrances. Roses, violets, jasmine, and lavender are just a few of the flowers commonly used in the perfume industry to make traditional perfumes and add a pleasing fragrance to lotions, soaps, candles, and more.

Medicines & supplements. Digitalis is derived from Foxglove (Digitalis purpurea) flowers and are used to treat heart arrhythmia. Chamomile flowers are used to make teas other types of supplements that calm anxiety, settle stomachs, and even relieve mouth sores caused by cancer treatments.

Note: This is the fourth post in a series exploring the science and agricultural importance of plant parts.

-Cindy

 

 

 

 

 

Science 101: Leaves

Leaves are the workhorse of plant parts. They produce the food plants need to grow and reproduce. Leaves protect plants from predators. They remove carbon dioxide from the air and produce oxygen for humans and animals to breathe. In addition to all of these important functions, leaves also serve as an important food source for animals, insects, and people.

Leaves convert energy from the sun into chemical energy through photosynthesis that the plant can use as food. This important process happens in chloroplast cells. Chlorophyll within these cells absorbs sunlight to turn water (H2O) and carbon dioxide gas (CO2) into sugar and oxygen gas (O2). Chlorophyll pigment absorbs red and blue light from the sun. Green light is reflected, which makes the leaves appear green.

 

A leaf is made of many layers that are sandwiched between two outer layers of tightly packed cells, called the epidermis. The epidermis is coated with a waxy substance called the cuticle. The epidermis and cuticle protect the leaf from insects, bacteria, and other pests and help keep moisture in the plant from evaporating too quickly.

Among the epidermal cells are pairs of sausage-shaped guard cells. Each pair of guard cells forms a pore called stoma. Carbon dioxide enters and oxygen exits through these pores. They also regulate water movement and cool the plant through the process of transpiration.

Veins support the leaf and are filled with vessels that transport food, water, and minerals to the plant. Monocot plants, like corn, wheat, and rice have long narrow leaves with veins that run parallel to each other across the length of the leaf. Beans, peas, and other dicot plants have wider leaves with veins arranged in a branched or webbed pattern. The petiole, or leaf stem, attaches the leaf to the plant’s stem.

Cabbage, lettuce, kale, and other leafy greens are some of the most well-known leaf crops, but there are quite a few other leaves that farmers grow for food and fiber. Here’s a look at a few products that wouldn’t be possible without leaves.

Medicine: Some leaves have important medicinal properties. Digitoxin from the leaves of the digitalis plant (i.e. foxglove) strengthens contractions of the heart muscle and is used in medicines to treat heart failure. Vincristine from the periwinkle plant (catharanthus rosea) is a chemotherapy medication used to treat many types of cancer.

Aloe. If you’ve ever had a sunburn, I’m sure you are familiar with the cooling and healing properties of aloe vera. The leaf sap of this succulent has a long history of being used for medicinal purposes dating back to ancient Egypt. Today, aloe vera is grown in tropical climates worldwide.   

Tea. Leaves of the tea plant (Camellia sinensis) are used to make most traditional caffeinated teas, including black tea, white tea, oolong tea, and green tea. The types are differentiated by how the leaves are processed after they are harvested. Generally speaking, white teas are plucked and dried, green teas are steamed and then dried, oolong teas are lightly roasted and then dried, and black teas are roasted and then dried.

Tequila. This popular distilled beverage is made from the blue agave plant, primarily grown in the area surrounding the city of Tequila in western Mexico. The region’s red volcanic soils are well suited to growing blue agave. More than 300 million plants are harvested there each year.

Herbs. The leaves of rosemary, thyme, oregano, basil, cilantro, parsley, mint and others can be harvested and used fresh or dried, packaged, and sold to use in flavoring food.

Essential Oils. Many popular essential oils including lavender, eucalyptus, and rosemary oil are derived from the leaves of their namesake plants through steam distillation and other methods.

Fiber. Although stems and seeds more commonly used as fiber, the leaves of sisal (Agave sisalana) and a few other plants provide good quality fiber for manufacturing rope, twine, rugs, and other fiber products.  

Celery. A celery stalk, the part that we eat, is a special part of the leaf called a petiole. The petiole, or leaf stem, attaches the leaf blade to the plant’s stem.

-Cindy

Note: This is the third post in a series exploring the science and agricultural importance of plant parts.

Science 101: Stems

Stems. They may not be as showy or as talked about as other plant parts, but they are important. Stems are the glue that keeps all of the parts together and working as a team.

Stems provide support and elevation for leaves, flowers, and fruits. They arrange leaves in a way that they can get adequate sunlight to perform photosynthesis, a process necessary for life. They position flowers to attract pollination and ensure that fruits have room to grow and ripen in the sun.

Stems transport fluids throughout the plant. They move water and nutrients taken up by the roots to the leaves. This upward movement happens in specialized cells in the stem called xylem. Stems also move the food produced by the leaves to other parts of the plant. The cells that do this work are called the phloem. Unlike xylem cells, phloem moves food up and down.

Stems can also store water or nutrients. Cacti are the best example of water-storing stems.  Their thick, hard-walled, succulent stem stores water, which is infrequent in the dry, arid, locations they thrive.  The inside of a cactus stem can be spongy or hollow. The outside is covered with a thick, waxy coating, which keeps the water from evaporating like it would in other plants.

Not all stems are found above ground. Nutrient-storing stems are located underground. Potatoes and sweet potatoes, for example, store excess energy in underground modified stems called tubers. These plants produce more energy than the growing plant can use at one time. Excess energy in the tubers and provide the plant energy to regrow in the spring.

There are quite a few other stems that farmers grow for food and fiber. Here’s a look at a few products that wouldn’t be possible without stems.

Wood and wood products, like paper, rank just behind food plants in overall value to society. Like all stems, a tree’s trunk is made up of xylem and phloem cells. Each year, the tree forms new cells, arranged in concentric circles called annual rings. Early in the growing season, the cambium produces numerous large cells that form the light-colored springwood. Towards the end of the summer, growth slows down and the cells produced are small with thick walls. These cells form the darker-colored summerwood. This process repeats each year, increasing the diameter of the tree and producing a valuable agricultural product.

Sugar. Sugar cane is a tall perennial grass grown in tropical environments like Florida and South America. The plant stores excess energy as sugar in a sweet juice found in the plant’s fibrous stalks (stems). To produce table sugar, the stalks are harvested, the juice is extracted, excess water is evaporated, and the sugar crystals are dried. While sugar cane is the number one source of sugar, it is important to note that it can also be made from sugar beets, a root crop.

Cinnamon comes from the inner bark of the trunk (stem) of cinnamon tree. Farmers will shave off the outside bark of the tree to get to the cinnamon layer that is harvested and dried. Cinnamon has a natural tendency to curl as it dries, which gives cinnamon sticks their curled appearance.

Straw is a byproduct of cereal grains like wheat, barley, and oats. When the seeds of these crops are harvested the stems, or stalks, are left behind. Most of the stalks’ nutrients were depleted while producing seed, leaving little nutritional value as a feed source. The stalks can, however, be baled and used for straw.

Maple Syrup. Pure maple syrup begins as sap from the xylem of a Sugar Maple tree. The sap is harvested in the spring when days are warm and nights cool below the freezing point. Trees are tapped, and the sap either drips into a bucket or flows down a special tube to a holding tank. Maple sap is clear, slightly sweet, and very thin. The distinctive maple flavor and thick consistency of syrup is developed through careful heating to evaporate most of the water. It takes 40 gallons of sap to make one gallon of syrup.

Onions & garlic. Although usually referred to as root crops, onions and garlic are both underground stems, called bulbs. Like tubers, these modified stems hold nutrient reserves for the following season – and provide a tasty food crop for us!

-Cindy

Note: This is the second post in a series exploring the science and agricultural importance of plant parts.

Science 101: Roots

Roots. They are the hidden heroes of plants. We rarely see them, but they provide the foundation from which all plants grow. Without them, we would not have fruits, vegetables, grains, wood products or beautiful flowers to enjoy.

Roots have two primary functions. They collect water and nutrients, and they provide anchorage and support for the plant. Both of these functions are essential. Plants cannot grow and produce flowers and fruit without water and nutrients, and plants would blow away without being anchored in the ground by roots.

The shape, size, and structure of roots vary greatly from species to species, but they are generally categorized into two main types – fibrous and taproot. Most dicots, or broad-leaf plants have a taproot system, and most monocots, like corn, wheat, asparagus, and rice have a fibrous root system.

Credit: United Soybean Board

Plants with taproots have a thick, main root that grows deep into the soil and smaller lateral roots growing from it. Some plants, like radish, have relatively shallow taproots with very small lateral roots. Others have a very deep primary root and an extensive system of lateral roots growing from it. The taproot system of soybeans, for example, can reach 6 feet deep with lateral roots that spread 1-2 feet wide in favorable conditions.

Some plants, like carrots, parsnips, and beets, have an extra thick taproot that hold large quantities of nutrients. These enlarged roots store extra sugars and other carbohydrates for the plant and provide a valuable food crop for us!

In contrast, a fibrous root system is usually formed by a network of thin, branching roots of about equal diameter. Plants with fibrous root systems often form a mat of roots underground. While they do not have a large taproot as an anchor, their many small roots firmly secure them in the ground.

Plants with shallow fibrous roots, like grasses, are also great at stabilizing the soil and preventing erosion. This makes them a good choice for cover crops, terraces, buffer strips, and other conservation practices.

Not all fibrous root systems are shallow. Corn roots, for example, often grow three to five feet deep. Some have even been found extending more than 10 feet!

Roots grow from their tips and are thin at first. New and rapidly growing portions of a root system are the most permeable and have the greatest ability to absorb water and nutrients. These thin roots are often covered with even smaller roots called root hairs. They may be small, but root hairs are numerous and mighty! Their large surface area to volume ratio makes them very efficient in absorbing minerals and water.

A common feature of almost all root systems is mycorrhizae, a symbiotic relationship that forms between fungi and plants. Plant roots secrete compounds that interact with microorganisms in the soil. In exchange for a bit of sugar, the fungus helps the roots pull in more nutrients and water than the plant could on its own. Mycorrhizal fungi occur naturally in soil and can be added as a seed treatment before planting.

Roots are influenced by the soil in which they live and are good indicators of soil health If the soil is compact, is low in nutrients or water, includes high populations of root pathogens, or has other problems, plants will not develop a healthy root system. On the other hand, roots also benefit the soil in which they grow. Roots help keep soil in place, add organic matter, and feed beneficial bacteria and fungi.

Healthy plants are essential for good crop yields…and healthy plants have healthy roots.

– Cindy

Science 101: Plant Classification

Plants are pretty amazing. They provide us with oxygen, food, fiber, and medicine. They grow in all regions of the world. Each species has leaves, stems, flowers, roots, fruit and seeds adapted to its habitat. These specialized plant parts ensure they can acquire their basic needs, protect themselves against predators, and reproduce.

In future posts, we will explore the function, specialized features, and agricultural importance of each of the basic parts of plants – roots, stems, leaves, flowers, and fruit. But before I dive into these topics, we need to take a step back and review some terminology – particularly in regard to how plants are classified.

Do you remember learning about Carl Linnaeus in high school biology? Linneaus is known as the father of taxonomy – a system for organizing the natural world. He brought order and structure into the previously chaotic realm of naming plants and animals. His system was based on morphology, a fancy word for grouping organisms based on their physical form and structure.

Today’s taxonomic system includes three domains: Archaea, Bacteria, and Eukarya. The Eukarya domain is divided into four kingdoms: Animalia (animals), Plantae (plants), Protista (slime molds, algae, and protozoans), and Fungi. Each kingdom is further divided into phyla (also called divisions), classes, orders, families, genera, and species. My biology teacher taught us to remember the order of classification with this mnemonic device: Did King Phillip Come Over For Good Soup?

Using corn as an example, the chart above illustrates how groups become smaller as you move down classification levels from domain to species. Two plants within the same group have more in common and are more closely related than they are to plants in another group. Just like humans are more closely related to gorillas and chimpanzees than other mammals.

Taxonomic classification is not just useful for plant identification. Understanding the common characteristics of plants within a group helps plant breeders, chemists, and others improve agricultural practices. For example, herbicides have been developed to kill broad-leaf weeds (dicots), without harming monocot crops like corn, wheat, and rice.

Since plants within the same family have similar roots, reproductive structures, or other characteristics, they tend to have similar growth characteristics, nutritional needs, and pests. Knowing this, farmers often rotate crops from different plant families to interrupt pest life cycles and reduce yield loss.

If this piqued your interest, be sure to check out our other Science 101 posts and subscribe so you don’t miss future posts.

– Cindy

Science 101: Pollination

The goal of every living organism, including plants, is to create offspring for the next generation. Flowering plants reproduce by seed, and to produce seed, pollination must occur.

So, what is pollination?  It is the transfer of pollen from the male flower part of the plant, the stamen, to the female part of the plant, the pistil.  Both of these parts are contained in flowers, sometimes the same flowers and sometimes different flowers.  I’ll go into more detail about types of flowers and their parts in a future blog post.

Most plants rely on wind or pollinators to transfer pollen, but some plants can pollinate themselves.

Soybean plants are self-pollinated. This means that pollen produced within a flower fertilizes the ovary of the same flower on the same plant. Because soybeans plants do not need to attract pollinators, their flowers are not showy. Soybean flowers are hidden under the leaves near the plant’s main stem. Each flower is only about the size of your pinky fingernail, but there can be 50 to 75 flowers on one plant.  Other self-pollinating crops include lima beans, green beans, peas, and peanuts.

Corn and other cereal grains, including wheat and rice, are pollinated by wind.  Corn plants have two types of flowers.  The ear is the female flower. The tassel at the top of the corn plant is the male flower. Wind carries pollen from the tassel to the silks at the end of each immature ear. Pollen grains attach to the sticky end of each silk, and travel down the silks to fertilize each ovary. After pollination, the ovary develops into a kernel of corn at the other end of each strand of silk.

Wind pollinated plants usually have long stamens and pistils with small or no petals. They also have very lightweight and smooth pollen that is easily carried by the wind from one plant to another.

Approximately 35 percent of the food and fiber crops grown throughout the world depend upon pollinators for reproduction. While bees are the most well-known, moths, butterflies, beetles, ants, bats, and hummingbirds are also pollinators. In fact, there are more than 200,000 different species of pollinators, and 1,000 of those are small birds and mammals.

Plants that rely on pollinators tend to have showy or fragrant flowers to lure insects, birds and other pollinators to them.  Food, in the form of energy-rich nectar and/or protein-rich pollen, also entices pollinators to visit flowers. Pollen grains stick to the pollinator’s body and hitchhike a ride to another flower. There, the pollen comes off on the top of the pistil and pollination occurs.

Our world is filled with flowers of many shapes, sizes, and colors, thanks to the many ways that flowers are pollinated.

-Cindy