Category Archives: Front List

Five things everyone should know about . . . The Soils of Wisconsin

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1 l Wisconsin’s soils were first mapped more than a century ago. The first soil map of Wisconsin was also the first ever made in the United States. It was produced in 1882 by geologist T.C. Chamberlin. In 1926, CALS soils professor Andrew Whitson created the second state soil map for his book Soils of Wisconsin. The third map followed 50 years later, compiled by eminent CALS soils professor Francis Hole. Since that time much new information and many insights have been gained, and these have been summarized in a fresh edition of The Soils of Wisconsin.

2 l The soils of Wisconsin are highly diverse. Nearly 80 percent of the state is covered with glacial deposits that differ in texture, composition, thickness and age (the Driftless Area, in western Wisconsin, was not glaciated in the most recent glacial period). There is a strong relationship between the soils and parent materials. The history of human impacts on soils in Wisconsin extends back 13,500 years but became intensified during the Late Woodland period (1,600 to 500 years Before Present) when fires were used to clear land, and further intensified in the mid-1800s when European settlers arrived and land clearing and large-scale crop production began.

3 l Many of Wisconsin’s soils are unique. There are more than 700 soil series (groups of soils with similar properties) in Wisconsin, and of these, 20 percent are considered endemic, having developed here through a unique combination of geology, plant communities and other factors. The “tension zone” between Wisconsin’s northern and southern forests contains 40 percent of these endemic soils while covering just 13 percent of the state’s land area. This zone also marks a transition not just in vegetation but in soil. The soils of the prairie, or Mollisols, mainly occur below the tension zone, and acid Spodosols, which often are forested, exist above it.

4 l Soils are affected by changes in climate. The melting of glaciers 11,000 years ago is a climatic event that affected Wisconsin’s soils, depositing millions of tons of glacial till and windblown, silty soil. For the future, we expect rising temperatures and increasing rainfall that will affect our soils and land use. In the winter, soils will cool more because of thinner snowpacks and less protection from freezing. The warming up will result in land use changes. Corn and soybean, for example, might be grown in areas that previously were unsuitable.

5 l Our soils yield profits. The soils in Wisconsin have a high yield potential and support an $88 billion industry. We observe highly significant correlations between the soil and such economic parameters as agricultural land value sales and adjusted gross income in every county of the state.

Layered features of vertically exposed prairie soil are pictured during a soil science class field trip to the University of Wisconsin-Madison’s Arlington Agricultural Research Station on May 27, 2014.
Photo credit: Jeff Miller/UW-Madison Communications

Five things everyone should know about… Sloths

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1) A sloth is not a sloth. There are two types of tree sloths that diverged roughly 20 million years ago—two-toed and three-toed sloths, so named for the number of digits on their forelimbs. They differ greatly in what they eat, when they’re active, the trees they use, how far they move and even their mating systems. In a nutshell, two-toed sloths are generalists, using a wide variety of habitat types and resources, while the three-toed sloth is much more specialized, eating leaves from just a few species of trees, and even spending the majority of their lives in just a few individual trees.

2) They are extremely low-energy. Both types of sloths have slow metabolisms, but the three-toed sloth has the lowest energetic needs of any mammal ever recorded. Sloths achieve this by not moving very much, and also by letting their body temperatures fluctuate with outdoor temperatures. In terms of calories, a single potato is all a three-toed sloth would need each day to survive (if sloths actually ate potatoes).

3) Constipation is a way of life. Sloths consume plenty of fiber in the form of leaves (three-toed sloths) and a variety of leaves and fruits (two-toed sloths). Yet these foods are digested so slowly that sloths need to pass feces and urine only about once a week. Three-toed sloths climb down to defecate at the base of their host trees—practically the only time they leave the canopy.

4) The sloth is a miniature ecosystem. And understanding that ecosystem helps clarify sloths’ odd bathroom behavior. Sloths host a dedicated species of algae in their fur as well as scores of flightless “sloth moths” that depend on the sloth’s defecation descent for reproduction. The moth lays eggs in the sloth’s dung and then returns to the sloth’s fur. After the eggs hatch, the caterpillars feed on the dung, become moths, and the moths find—during the only brief moment in their lifetime that they can fly—another sloth to live on. When the moths die, their bodies are decomposed by fungi and bacteria in the sloth’s fur. The products of this decay, nitrogen in particular, provide fertilizer for the algae, which the sloths eat—thus adding nutrients to their diet.

5) Made for the shade. As tropical forests in Central and South America are cleared for agriculture and other uses, sloths (like many other species) need to find or adapt to new habitats in order to survive. Our team studied sloth populations at a large shade-grown cacao plantation in Costa Rica. With its diverse overstory of native trees, the plantation provides suitable habitat for sloths—especially two-toed sloths—and seems to point the way to at least one kind of farming that can benefit sloths and other native tropical animals.

Jonathan Pauli and Zach Peery, professors of forest and wildlife ecology, have studied sloths in Costa Rica since 2009.

PHOTO: Jonathan Pauli watches after releasing a two-toed sloth in Costa Rica
Photo courtesy of Jonathan Pauli

Five Things Everyone Should Know about … Nutmeg

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1 It’s not a nut. Nutmeg is the seed kernel inside a yellow fruit of the nutmeg tree, an evergreen native to the Molucca Islands (sometimes called the Spice Islands) of Indonesia. Whole nutmeg seeds are oval, brown and about an inch long, with a nutty aroma and taste—but they don’t pose a risk to people with nut allergies.

2 This beloved holiday spice can be dangerous. But only in fairly large amounts. It takes two tablespoons or more to produce symptoms of nutmeg poisoning, toxicologists say. Those symptoms may include acute nausea, dry mouth, dizziness and a slowdown of brain function to the point where victims experience blackouts. Higher doses can cause shock and hallucinations.

3 That’s due to the nutmeg’s essential oil. Myristica, as the oil is called, contains myristicin, a narcotic that functions in the plant as a natural insecticide. Nutmeg also—as do its frequent recipe companions, cinnamon and clove—acts as an antibiotic.

4 Nutmeg has other medicinal properties as well. Consumed in small doses, nutmeg can serve as a digestive aid in reducing flatulence and indigestion, and can also help treat nausea and diarrhea as well as lower blood pressure. Applied topically, it can offer pain relief and has been used for rheumatism, mouth sores and toothache.

5 Nutmeg was more valuable than Manhattan. By the 16th century, nutmeg—coveted as a flavoring, hallucinogen, alleged aphrodisiac and deterrent to the plague—was being sold by European traders at a 6,000 percent markup. The Dutch soon wrested control of all the nutmeg-producing Moluccas except for a tiny island called Run, which was controlled by the British. At that time, Run seemed more valuable than Manhattan, then under Dutch control as New Amsterdam. In order to seal their nutmeg monopoly, the Dutch gave the British New Amsterdam in exchange for Run. It seemed like a good idea.

Johanna Oosterwyk, a faculty associate in the Department of Horticulture, is manager of the DC Smith Greenhouse, a facility that provides plant-growing space for the instructional needs of departments and programs of the College of Agricultural and Life Sciences.

Five things everyone should know about … Stevia

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  1. It’s not just a sweetener. The plant genus Stevia includes more than 200 species of herbs and shrubs native to South America and mexico. Yet only two species, Stevia rebaudiana and Stevia phlebophylla, produce steviol glycosides in their leaves. These glycosides are the source of the plant’s sweet compounds.
  2. But as a sweetener, it’s nothing new. Stevia rebaudiana has been used for more than 1,500 years by various indigenous peoples in South America both to treat diabetes, obesity and hypertension and to provide a sweetening effect for food and drink. Commercial use of stevia took off when sweeteners such as cyclamate and saccharin were identified as possible carcinogens. Japan became the first country to introduce commercial use of stevia in the early 1970s and still consumes more of it than any other nation. Stevia has been available for several decades in natural food stores but in recent years has increased greatly in popularity as a sweetener for processed foods. Today, stevia can be found in many u.S. supermarkets under a variety of brand names, such as Truvia and PureVia.
  3. Why use stevia instead of sugar or other sweeteners? Stevia is significantly sweeter than table sugar, and comparable in sweetness to products such as aspartame, saccharin and sucralose, but it is metabolized differently. Stevia is perceived as sweet but does not cause a rise in blood glucose like sugar, making it a promising food for diabetics. It is a natural rather than an artificial sweetener.
  4. How is stevia processed within the body? The glycosides in stevia are primarily known as rebaudioside (or rebiana) and stevioside. They have some bitterness associated with them and can be blended with other compounds to minimize this effect. Once consumed, the glycosides break down into steviol, which is simply excreted; and glucose, which is used by intestinal bacteria and does not go into the bloodstream. So eating foods sweetened with stevia means a sweet taste without added calories.
  5. Can I grow stevia in Wisconsin? Stevia plants are not adapted to cold conditions but may be grown as annual plants in temperate regions (including in Wisconsin). However, growing plants from seed as an annual crop generally does not result in satisfactory results. Stem cuttings from mature stevia plants may be rooted and used to propagate stevia for growth in spring and summer.

Irwin Goldman is a professor and chair of the Department of Horticulture.

Five things everyone should know about . . . Milkweed

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1. It is the stuff of life for monarch butterflies. Monarchs lay their eggs on milkweed, and milkweed leaves serve as nearly the sole food of monarch caterpillars. But many species benefit from the bounty of milkweed. Milkweed flowers produce nectar that other kinds of butterflies, honey bees, native bees and other pollinators enjoy. Hummingbirds line their nests with floss from milkweed seed pods.

2. It’s both medicine and poison. Milkweeds—there are more than 100 species—belong to the genus Asclepias, named after the Greek god of medicine and healing. Milkweeds have been used in medicine for thousands of years because their tissue contains cardiac glycosides, which increase the heart rate and in a purified form are useful in treating such conditions as cardiac arrhythmia and congestive heart failure. As a crude extract, cardiac glycosides are toxic and have been used as poison. Monarch larvae retain the toxins they consume in milkweed leaves and as butterflies remain toxic to predators.

3. Its presence is dwindling, along with the monarchs. The first decade of this century saw a 58 percent decline in milkweeds in the Midwest, according to a 2012 study—a time when we’ve also seen a whopping 81 percent decrease in monarch production. Factors often cited for milkweed’s decline include loss of habitat as grasslands and conservation reserves have been converted to farmland for corn and soybeans as well as increased use of herbicides on those crops.

4. There’s a growing movement to bring it back. Researchers at CALS and elsewhere have noted an increase in biodiversity, pollination and other ecosystem services that come from establishing or maintaining a mix of perennial native plants near cropland—and milkweed, they say, should be part of it. Vigorous efforts are taking place throughout the Midwest to plant large areas of milkweed along the monarchs’ migration path to Mexico, where they spend the winter.

5. Milkweed will enliven and beautify your garden—but keep your gloves on when handling. The toxins that protect the monarch can harm humans. Make sure the sap doesn’t get into your eyes, and if it does, seek medical attention as it can cause significant damage. While not all milkweeds are equally toxic and some kinds can be eaten, great care must be taken when selecting and preparing it.

 

Five things everyone should know about gluten

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1. What is it? Gluten is a substance composed of two proteins—gliadin and glutenin—that are found in the endosperm (inner part of a grain) of wheat, rye, barley and foods made with those grains, meaning that gluten is widespread in a typical American diet.

2. Is it harmful? People who suffer from celiac disease, an autoimmune digestive disorder, are unable to tolerate gluten. Even a small amount of it (50 milligrams) can trigger an immune response that damages the small intestine, preventing absorption of vital nutrients and potentially leading to other problems such as osteoporosis, infertility, nerve damage and seizures.

3. How widespread is celiac disease? An estimated 1.8 million Americans have celiac disease; as many as 83 percent of those suffering from it remain undiagnosed or are misdiagnosed with other conditions. Another 18 million (about 6 percent of the population) do not have celiac disease but suffer from gluten sensitivity. They report such symptoms as diarrhea, constipation, bloating and abdominal pain—which also are symptoms of celiac disease—but do not experience the same intestinal damage. For those with celiac disease or gluten intolerance, a gluten-free diet is beneficial.

4. Should you cut gluten from your diet even if you don’t have these conditions? Probably not. Restriction of wheat in the diet often results in a decrease in the intake of fiber at a time when most Americans consume significantly less than the recommended amount. Low-fiber diets are associated with increased risk of several acute gastrointestinal diseases (examples: constipation, diverticulosis) and chronic diseases such as heart disease and colon cancer. If not done carefully, gluten-free diets also tend to be low in a number of vitamins and minerals.

5. Don’t diagnose yourself. The broad range of symptoms associated with celiac disease and gluten sensitivity may be due to other causes; self-diagnosis and treatment of perceived gluten intolerance may delay someone from seeking more appropriate medical care. The only way to know for certain if you have celiac disease is from a blood test for the presence of specific antibodies followed by a biopsy of the small intestine. If you are experiencing the symptoms described above, please seek medical care.

Beth Olson is a professor of nutritional sciences. Her principal research areas concern breastfeeding support and improving infant feeding practices in low-income families.

Five things everyone should know about … Industrial Hemp

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1. It’s a booming industry.  The American hemp industry generates sales of $450 million a year, according to the Hemp Industries Association—about a quarter from food and body care products and the rest from a wide array of goods, including clothing, auto and airplane parts, building materials and more. But since the cultivation of hemp is illegal in the United States under federal anti-drug laws, all hemp and hemp parts (fiber, oil, seed) used to make these products have to be imported.

2. It’s cannabis, but not the narcotic kind. Hemp is of the same plant species as marijuana, Cannabis sativa, but it is bred and cultivated quite differently. Cannabis bred for narcotic use is high in tetrahydrocannabinol (THC), the plant’s main intoxicant, while in hemp THC content is far lower, not nearly enough to produce a high. Also, hemp can be grown densely since the fibrous stalk is the main harvest, while marijuana plants need room to spread out and grow buds, which contain the most THC.

3. It’s been with us a long time. Hemp was cultivated in China more than 4,000 years ago, making it one of the oldest domesticated crop plants. It originated in Asia, spread to Europe, and came to the U.S. with the first European settlers. Primarily a fiber crop, hemp also was used for food and medicine. Many of the earliest domesticates had multiple uses in human societies, and hemp is an excellent example. Over time and geography, hemp cultivars found separate, specialized uses for fiber production and medicinal purposes.

4. It was huge in Wisconsin. Farmers were growing hemp in Wisconsin before it was admitted as a state, but true hemp glory came during World War II, with high demand from the military for such hemp-based products as rope and twine (eventually some 146,000 acres of hemp were harvested nationwide). The biggest growing areas were in
Fond du Lac, Green Lake, Dodge and Racine counties. An article in the Madison-based Capital Times in 1941 noted that Wisconsin produced more than 75 percent of the hemp raised commercially in the United States, and Wisconsin was referenced several times in the 1942 government-produced film “Hemp for Victory.” At one point Waupun-based grower and mill owner Matt Rens was known as “America’s Hemp King.” But after the war the crop lost much of its value, especially with the rise of synthetic fiber, and in 1970 federal drug law classified plants with any THC as an illegal substance.

5. There’s a growing push to change that. The Industrial Hemp Farming Act of 2013, introduced in both the House and Senate, would amend federal drug law to legalize growing cannabis that contains less than 0.3 percent THC. It enjoys the support of Senate Minority Leader Mitch McConnell (R-KY) and Senator Rand Paul (R-KY), among others.

Irwin Goldman is a professor and chair of the CALS’ Department of Horticulture. He is the nation’s only publicly supported beet breeder.

Five things everyone should know about… Hazelnuts

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1   They’re crazy nutritious and gluten-free. Hazelnuts are rich in vitamins (particularly vitamin E and B-complex groups of vitamins, including folates, riboflavin, niacin, thiamin) as well as dietary fiber. Like almonds, they are gluten-free. They also are rich in monounsaturated fatty acids such as oleic acid and linoleic acid, which help reduce LDL, the “bad” cholesterol, and increase HDL, the “good” cholesterol.

2   An exciting market beckons. Hazelnut oil serves various purposes in the kitchen (most notably as salad and cooking oil) as well as in cosmetics and pharmaceuticals. Kernels can be eaten fresh; used in baked goods, confections and other edibles; or ground for use in nut flours. An appetite is growing for spreadable hazelnut butters (Nutella, anyone?). And then there’s biofuel—the high oleic acid content makes hazelnuts an excellent feedstock for biodiesel and bio-industrial products.

3   They’re good for the environment. As a long-lived woody perennial, hazelnut bush plantings can be used to stabilize sensitive soils and erodible sites. Plantings do not have to be reestablished for decades. They can be closely associated with other high-diversity approaches to agriculture, including agroforestry and multicrop plantings. Since American hazel is a prominent native, there is no risk of invasiveness, and interrelationships to support Wisconsin wildlife are well established. In addition, hazel production readily integrates with small and medium-sized farming operations and family/cooperative farm unit organization.

4   Growers are emerging in the Midwest, including in Wisconsin. Southern Europe is still king in world hazelnut production, with Turkey leading at 75 percent. In the United States, commercial hazelnut production is still limited to the Pacific Northwest, where the climate allows for growing European cultivars. But a number of Midwestern farmers are trying their hand with two species, American (Corylus americana) and beaked (Corylus cornuta), that do well in cold climates and sandy soils. Surveys have identified about 130 hazelnut growers in Wisconsin, Minnesota and Iowa, with nearly 135 acres in production.

5   Important genetics work is underway. Farmers now growing Midwestern hazelnuts are also growing important data as there are, as yet, no commercially proven cultivars of hazelnuts in this region. Breeders are working to develop genotypes focusing on both pure lines of native American hazel and on hybrid crosses between European and American. By selecting from the very diverse native populations and by crossing European with American, they hope to develop a hazelnut shrub with the nut quality and yield of the European and the cold-hardiness and disease tolerance of the American.

 

The Midwest Hazelnut Development Initiative (UMHDI, midwesthazelnuts.org) is a regional collaboration that includes representatives from UW–Madison and UW-Extension.

Jason Fischbach, an agriculture agent with UW-Extension and a program partner with UMHDI, contributed to this piece.

Five things everyone should know about . . . Spotted Wing Drosophila

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1.  There are 113 species of fruit flies. Why worry about this one? While most other fruit flies attack only overripe or damaged fruit, the female spotted wing drosophila can cut a slit and lay eggs in healthy fruit. Typically this insect will strike just as the fruit begins to color. It prefers such soft-skinned fruits as raspberries, blueberries, strawberries and blackberries.

2.  What’s been the regional damage so far? This native of eastern Asia, which began proliferating on the West Coast about four years ago, was first spotted in Michigan in 2010, where it has caused problems in cherries, blueberries, raspberries and strawberries. Untreated fruit will begin decay within three to four days of egg laying and have numbers of small white larvae (maggots) inside when harvested.

3.  What have we experienced in Wisconsin? Drosophila suzukii was first reported in adult fruit fly traps in Wisconsin in 2010, but no damage was seen until last August, with major crop losses in fall raspberries, blackberries and late strawberries in at least 15 counties. Cranberries, thankfully, have been spared so far, possibly due to the thickness of that fruit’s skin.

4.  What are the challenges of controlling this pest? The insect must be killed before eggs are laid in the fruit; eggs and larvae inside the fruit cannot be controlled by sprays. There are treatments that can be used to control this insect in organic production, but multiple sprays and thorough coverage are needed. We do not know if this insect is capable of surviving our winters or can be brought in on southerly winds or infested produce from out of state.

5.  What actions are we taking during the coming growing season? The use of vinegar-based adult fruit fly traps will help growers determine when the spotted wing drosophila first appear in their fields. Treatments must be started on sensitive crops when the first flies are captured.

Phillip Pellitteri is a distinguished faculty associate in the CALS Department of Entomology and a UW-Extension specialist. He runs the Insect Diagnostic Lab, which was established to identify insects and insect-damaged plant material from around the state and recommend controls to both county UW-Extension offices and commercial concerns. He also teaches in the Master Gardener program.

Five things everyone should know about . . .The Tension Zone

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1.  You will not suddenly develop migraines upon entry. Rather, a “tension zone” describes a geographic area that marks a change from one type of vegetation to another, with species from both areas intermingling in that zone.

2.  There’s a pronounced tension zone in Wisconsin. It stretches in a loose S-shape from Burnett County in the north all across the state, ending in Racine County in the south. Wisconsin’s tension zone marks the crossover between the Northern Mixed Forest—closely related to the forests of northeastern Minnesota, northern Michigan, southern Ontario, and New England—and the Southern Broadleaf Forest, which is more like forests you’d see in Ohio and Indiana. In the tension zone you’ll find plants and animals representing both of these forest types. Before the landscape in the south was developed and converted to farms, you would have seen primarily open oak savanna with forest and prairie.

3.  It’s mostly about climate. The tension zone is marked by a
climatic gradient, with cooler, moister conditions to the north and relatively warmer, drier conditions to the south. Up to the 1800s, these southern conditions were more favorable to higher populations of Native Americans—and they were a greater cause of fire, both purposeful and accidental. This maintained more open conditions in the south.

4.  It’s a fruitful area for research. John Curtis, a famous Wisconsin plant ecologist, and his graduate students in the 1950s identified the tension zone as a place where relatively more plant species had their northern and southern range limits. His book, The Vegetation of Wisconsin (1959), talks about this and includes a map of the number of species reaching their limits in each county. Today, researchers are again very interested in the tension zone because of changes in land use that have endangered some native plant species. Also, with climate warming, the area is of interest to both climate scientists and plant ecologists, who are looking at how the tension zone is and will be moving north—and its potential effects on ecosystems.

5.  You’ll know you’re in the tension zone when you’re heading north and … oaks that are dominant in southern Wisconsin, such as Bur, black and white, meet up abruptly with red and white pine as well as paper birch and tamarack swamps that are more characteristic of the north. Shagbark drops out completely and bitternut hickory becomes much less common. You’ll start seeing some birds that are absent or relatively uncommon in the south: common loon, ruffed grouse, osprey, common raven, white-throated sparrow and purple finch. You’ll also encounter northern mammals: snowshoe hare, porcupine, red squirrel, black bear and timber wolf.

David Mladenoff is the Beers–Bascom Professor in Conservation in the Department of Forestry and Wildlife Ecology

Five things everyone should know about . . . Quinoa

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  1. This “supergrain” is not a grain. Quinoa (KEEN-wah) is not even in the grass family, unlike such grains as wheat, rye, oat and corn. As a member of the family Chenopodiaceae, the Andean plant’s closest relatives include beets and spinach. When prepared for eating, however, its seeds pass as a grain substitute to such an extent that quinoa is known as a pseudocereal. Quinoa may have been domesticated before the grasses and likely is one of humankind’s first seed domesticates in the Americas.
  2. It is super-nutritious. Quinoa has 10 essential amino acids, is very high in protein (up to 18 percent, compared with 10-12 percent for most grains) and is loaded with minerals including iron and magnesium. It is gluten-free and so nutritious that NASA researchers deem it an ideal food for long-term space missions. Quinoa seeds naturally contain saponins, which must be removed after harvest and prior to consumption. Saponins have an anti-nutritional effect on humans but provide bird-resistance to the plant, which allows it to be cultivated widely throughout the Andes. Most commercial quinoa available in North America has had its saponins removed prior to sale, rendering the seeds palatable and healthy.
  3. It was sacred to the ancient Incas. They called quinoa the “mother grain,” and each year the emperor would sow the first seeds using a golden ceremonial spade, historians say. The Incas cultivated quinoa at very high altitudes in the Andes, and some of the best quality quinoa today still comes from those high elevations. The Spanish called this crop arroz pequeño (little rice), but they favored other crops such as barley and oats above quinoa. Spanish colonists later dismissed quinoa as “food for Indians” and, because it was held sacred in non-Christian ceremony, for a time even banned it and forced the Incas to instead grow such European crops as wheat.
  4. Popularity brings problems. The new demand has been a boon for growers in Peru and Bolivia, who have seen prices for quinoa nearly triple over the past five years—but now fewer native consumers can afford it.
  5. Quinoa’s big moment is fast approaching. The United Nations recognizes 2013 as the International Year of Quinoa, an observance intended to promote its benefits and potential use. The crop is very tolerant to stress and can be grown in marginal environments, providing hope that quinoa can be used in the developing world to improve human nutrition and economic conditions.

Irwin Goldman is a professor and chair of the CALS’ Department of Horticulture. He is the nation’s only publicly supported beet-breeder.