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October 2009 Archives

What's Up With That?!

Birch Abnormal Growth Syndrome (BAGS) aka. Mouse Ear Disorder

Carl Rosen, Extension Soil Scientist and Karl Foord, Extension Educator

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The strange leaf symptoms on this river birch tree, taken on August 7 (Photo 1, left) were diagnosed as birch abnormal growth syndrome or BAGS. New leaves are severely stunted and take on a mouse ear appearance. For many years the cause of this disorder was a mystery, but it is now known to be due to a deficiency of nickel.

Photo 1 (left): River Birch 'Summer Cascade' at planting time showing symptoms of nickel deficiency (BAGS). Photo taken August 7, Karl Foord.


Nickel is an element only recently shown to be essential for plant growth and is required in very small amounts. Almost all soils have enough nickel to support plant growth, but under some conditions, nickel deficiency can still occur. The mouse ear symptoms on this river birch were first seen when growing in a peat-based container mix, and were initially misdiagnosed as bud damage from a late frost. However, after the tree was transplanted into the soil in mid-May, the symptoms, after continuing for the next few months, have now begun to appear normal.10-1-09_Med-Summer Cascade Birch mouse ear.j_CarlRosenpg.jpg


Based on research conducted at the University of Minnesota and in other areas of the country, BAGS almost exclusively occurs on river birch when grown in peat-based media and can be corrected by soil or foliar applications of nickel.

Photo 2 (right): Close up of 'Summer Cascade' river birch leaves with BAGS. Photo taken August 7, Karl Foord

Research has also shown that when soil is added to the peat media (20-30% by volume), the nickel deficiency symptoms will not occur, suggesting that there is enough nickel in the added soil to meet the nickel requirements of the plant.

10-10-09_Med_nickeldefonriver birch_carlrosen.jpgIn cases where the symptoms are most severe, an analysis of the peat has shown excessively high levels of zinc. These high levels of zinc in the peat likely accentuate the nickel deficiency. Therefore, adding soil to the peat mix may help by 1)alleviating BAGS symptoms by adding the needed nickel,  and 2) by tying up or diluting some of the excessive zinc in the peat.

Photo 3 (left): Up close. Mouse ear symptoms of nickel deficiency on peat-based media. Carl Rosen.

As shown by the picture taken on September 14 (Photo 4, below), the tree has nearly recovered from its mouse ear symptoms and is expected to make a complete recovery once the roots have fully established into the native soil. 

10-1-09_Med-Summer Cascade Birch 9 14 2009 recovered_KarlFord.jpgIn general, BAGS has been a problem most apparent to the nursery industry, as trees showing the symptoms are usually not sold. However, if the problem does occur in containers, it can be corrected with nickel applications or by transplanting to a medium containing at least 20% soil. Soils in Minnesota have enough nickel to support plant growth, therefore nickel application to river birch growing in the landscape is not necessary.

Photo 4 (left): Recovery of river birch 'Summer Cascade' from BAGS.  Photo taken September 14, Karl Foord.




Field Guides Can Be Fun

Jeff Gillman, Nursery Management Specialist

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Different people collect different things. Some like baseball cards, some like shoes, and some like coins. I like books about insects. No, really, I do. Just glancing up from my desk I can count something like 5 field guides, 10 general entomology texts, and a slew of others that fit into categories like insect control, insect taxonomy and insect physiology (I have a lot more at home). If you were to spend some time with these books you would discover rather quickly that, all in all, entomologists are boring writers. No zip, little spark. And that, in a nutshell, is why I like Jeff Hahn's new book Insects of the North Woods so much.


Photo and Cover: Insects of the North Woods, by Jeffrey Hahn. © Kollath-Stensaas Publishing.

Just looking at the cover of Insects of the North Woods you might be convinced that this is just a typical insect field guide. It's got some pretty pictures and, on the back, the obligatory author photo. But when you open the pages of this book, you quickly discover that it is not only as informative as you would expect from a University of Minnesota Entomologist, it's also entertaining. This book literally drips with Hahn's personality and sense of humor. Between talking about receiving a gift of a dead insect being every woman's dream when referring to scorpion fly mating rituals, and the mini scuba tanks that predaceous diving beetles use, you soon come to realize that this isn't just an entomologist reciting dry facts. Instead, this is an author who loves his subjects and who wants the reader to love them too. Like most people, I don't read field guides cover to cover, but with this book I have often found myself going through the book page by page because I don't want to miss one of Hahn's insightful comments (or one of his amusing analogies).

Besides the writing, this field guide has everything else that you'd expect a field guide to have, including great pictures (mostly by the author), a nice index system for finding the insect you're looking for, and a good, but not overly-done introduction. Though this guide concentrates on insects of the North Woods and so is, at least in theory, intended for use in northern Wisconsin, Michigan, and Minnesota, it is also the best book available for identifying insects in forests around the Twin Cities area and is a great first field guide for any budding entomologist. If you enjoy insects, or if you're just interested in knowing what some of the insects that flit about your trees are, then you shouldn't miss this book.

Airborne Aphids

Jeffrey Hahn, Asst. Extension Entomologist

10-1-09soybean aphid C.Difonzo.jpgMany people in Minnesota, including the Twin Cities, that spent time outdoors during mid-September encountered large numbers of small dark-colored 'gnats'.  Upon closer examination, these insects turn out to be winged aphids (examples include soybean aphids, basswood aphids,and oat bird cherry aphids).  This has been a favorable summer for aphids and large numbers were produced.

Photo (left): 'Winged and wingless soybean aphids on buckthorn in spring'.  Christina DiFonzo, Michigan State University, Bugwood.org.

While the relatively cool summer had only a minor impact on the development and reproduction of aphids, these conditions had a more significant effect on aphids' natural enemies, such as lady beetles.  The cooler weather slowed down their rate of reproduction which ultimately allowed aphid numbers to thrive.

Aphids have a very unusual and complicated life cycle.  Many typically live on two different host plants.  They spend the summer on their primary host (e.g. soybeans for soybean aphids) feeding on sap and producing many generations.  Aphids reproduce parthenogenetically, i.e.eggs are not fertilized and only females are produced.  Females give
birth to live young.  

The end of summer brings shorter day length.  When combined with a few days of below average temperatures, these events trigger the production of a generation of winged females aphids (winged males are produced about a week later).  This year, that cold weather occurred at the end of August.  These winged aphids take flight and look for their alternative host plant (e.g. buckthorn for soybean aphids).  It is this migration that people have been seeing recently.

Once aphids land on their second host, they produce several generations of wingless aphids.  When the males arrive, they mate and then the females lay fertilized eggs.  Most aphids overwinter in the egg stage.  When spring arrives, the eggs hatch into wingless females which produces two or three generations.  Eventually a winged generation is produced, and these aphids fly back to their original host plants to start the cycle all over.

A common question people have asked is whether these insects will bite. Even though they are gnat-like, the answer is no.  They are harmless to us and do not bite like a mosquito or black fly.  However, it is possible that they may taste test people by trying to insert their
mouthparts into us which can result in a mild prick.  Fortunately,aphids then realize that we are not food.  

People have also wondered whether using a mosquito repellent will help keep these aphids off of us.  Repellents are designed to hide our chemical scent from blood-feeding insects, especially mosquitoes.  Since aphids are not seeking us out to feed on us, but just encounter us randomly, repellents will have no effect against them.  However, they are attracted to the color yellow so one step you can take to reduce the aphids that land on you is to avoid wearing any clothes of yellow color.

There have been a few reports of people applying insecticides into the air to try to kill the aphids around their homes.  This, of course, is an entirely futile gesture and just puts the individual at more potential risk from an accident with pesticides.  People should not
attempt to spray the aphids in their homes.

Fortunately, this migration of aphids is a short-lived problem and goes away on its own.  The greatest numbers of aphids were out for about a week during mid-September and have noticeably declined since then.  By October, there should be very few still actively flying.


Lawn Care Tips for October

Bob Mugaas, University of Minnesota Extension Educator

Thumbnail image for 10-1-09picture 1_cropped_ bobmugaas.jpg1.Cease lawn mowing when temperatures are cool to cold and the grass shoot growth has essentially stopped. Reducing mowing heights to 2.0 - 2.5 inches for the last two or three lawn mowings of the season will reduce the amount of leaf tissue present over winter and can reduce the amount of snow mold that may occur. It is not necessary to collect clippings as long as they can filter down into the turfgrass canopy at the soil surface. Excessive amounts of grass clippings should not be left on the lawn surface in the fall or at any other time of the year.  Photo 1 (left). Lawn mowing should continue through the fall. Bob Mugaas.

2. A thin layer of leaves can be left on the lawn as long as they are ultimately chopped up as the lawn is mowed through the fall.

3. When confronted with several inches of leaves over the lawn, it is best to rake off the majority of those leaves before mowing and either compost them or use them as mulch material in other parts of the landscape. Thumbnail image for Thumbnail image for 10-1-09picture2_bobmugaas.JPG A thick layer of leaves left on the lawn blocks out sunlight to the grass and may even smother the existing grass beneath that layer resulting in large areas of thin or even dead grass come next spring. Photo 2 (left): Acceptable leaf cover that can be ground up adequately with a lawn mower. Bob Mugaas

4. Early October can still be an excellent time for controlling those pesky perennial broadleaf weeds such as dandelion and creeping Charlie.  Best control with most available herbicide products is achieved when daytime temperatures are above 50o F. but less than about 80o F. That's usually not a problem at this time of year.  Be sure that neither the grass nor the weeds you are intending to treat are under any drought stress. Drought stress will usually result in less than satisfactory control and may even injure the desirable lawn grasses because they can become susceptible to broadleaf herbicide injury under such circumstances. Always follow product label directions for proper use whether in the fall or any other time of the year.  Photo 3 (below and right). Young and mature dandelion plants are best controlled in the fall. Bob Mugaas
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5. In the Twin Cities, a late season application of nitrogen fertilizer should be put down around Halloween.  At this time of year, the nitrogen is taken up into the plant and stored in the crowns, rhizomes, tillers and/or stolons where it can be quickly accessed next spring by the growing grass plant. Follow this application with about ¼ to ½ inch of water to move the nutrients into the soil where they can be taken up by the roots. Never apply fertilizer to frozen ground. You would like about two to three weeks of unfrozen ground following this fertilizer application to allow for root uptake of the nutrients.


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6. As a general rule-of-thumb, it is best to avoid stimulating excessive shoot growth during late September to mid-October. Succulent growth associated with higher nitrogen levels, can contribute to increased incidence of snow mold over winter. A fertilizer application about the time of the State Fair provides the additional nutrients for the fall growth period, while the late season application is primarily stored for growth next spring. It is often easy to tell which lawn has had a late season application of nitrogen as they will usually be noticed as the first lawns with healthy growth and a dark green color in early spring. Photo 5 (above and left): Photo taken in early May. Dark green strip received a late season N application the fall before; surrounding turfgrass area did not. Bob Mugaas

 7. With the current dry period we are experiencing, regular watering should be continued throughout the fall period or until more frequent rainfall returns. While you may not need the one inch of water per week as during the summer months, applying that same amount during the fall may be sufficient for two or perhaps even three weeks depending on weather.10-1-09picture7_bobmugaas.JPG Late summer and the fall period are a naturally active growth period for our lawn grasses. Making sure they have ample water and nutrients during that time will aid their recovery from summer stresses and encourage healthy growth for the next growing season. Photo 6 (left). Lawn watering. Bob Mugaas.

Any reseeding of the lawn should have been completed by mid-September in the Twin Cities area. It is best to avoid seeding during the early to mid-October period, as the very young seedlings that do emerge often have poor survival over the winter. If you would still like to do some seeding, you can do what's known as dormant seeding. Before the ground is frozen, but while the soil is cold (so as to not encourage seed germination in the fall),  incorporate the seed into the soil surface. Incorporating the seed into the soil surface will help protect it through winter. Seed remaining in that 'dormant' condition until next spring, can get a head start on germination and growth for the next growing season. In the Twin Cities area, dormant seeding is usually done in early to mid-November depending on weather conditions

With a little effort and planning this fall, successfully preparing the lawn will help it survive the upcoming winter months, while also encouraging a healthy start for next spring. It may seem a little backwards, but preparation of a healthy spring lawn begins the previous fall. For additional information on any of the topics mentioned in this newsletter, please see the lawn care section in our Sustainable Urban Landscape Information Series website at www.sustland.umn.edu.


Put Your Garden to Bed Without Plant Pathogens

Michelle Grabowski, University of Minnesota Extension Educator

As the Minnesota growing season is winding down and first frost is just around the corner, many gardeners are starting to prepare their landscapes for the long winter ahead. Plants are making physiological changes that will allow them to survive Minnesota's cold winter and so are the plant pathogens that have plagued the garden this year. Many plant pathogens overwinter in infected leaves and herbaceous stems that will soon fall to the ground and become part of the leaf litter. Other pathogens survive in live plant tissue like perennial crowns and tree branches. Reducing the number of pathogens that survive from one season to the next is a great way to reduce potential disease problems in the next growing season. Sanitation, the removal of infected plant parts, is an important part of disease prevention. Although sanitation will not prevent all future disease (pathogens can often move in from long distances away), it can reduce the severity of disease or delay its appearance.

In the Flower Garden

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Photo 1 (left): Peony with a fungal infection on leaves and stems. M. Grabowski.

A wide variety of fungal and bacterial plant pathogens cause leaf spot and blight diseases in annual and perennial flowers. After the first frost hits, these infected leaves, stems, and flowers fall to the ground. The pathogens spend their winter nicely insulated within this old plant tissue, covered by snow. In the spring, warming temperatures and moisture from spring rains and melting snow stimulate the pathogens to start reproducing. Fungal spores and bacterial pathogens are then soon being splashed or blown onto the newly emerging plant shoots, starting the disease cycle all over again.

What can a gardener do?

  • Scout your gardens now and take note of any plants with leaf spot or blight diseases. Even mild cases are worth addressing now.
  • Do not bother spraying fungicides at this time. It is too late. Fungicides are protective and preventative in nature. They may be useful early in the season to protect young growing tissue but are unnecessary as the plants go dormant.
  • After the first hard frost, go back to each infected plant and collect all of the fallen leaves. Cut herbaceous stems back to the ground. Remove all of this infected plant material from the garden.
  • Infected plant debris can be composted if the compost pile heats up to 160 degrees F. Don't forget to check with municipal compost facilities. These are often more intensely managed than a backyard compost pile and are often an acceptable place to take infected plant material. If composting is not an option, infected plant material can be buried to speed up decomposition or thrown away with the trash.
  • If any perennials are found to be infected with a virus or with aster yellows, remove the plant. These pathogens survive in the live crown of the plant. Once infected, the plant will always carry the disease. Virus and aster yellows infected plant material can be composted since these pathogens do not survive without a live host plant.

Trees and Shrubs

10-1-09black knot arb 2 (Medium)M_Grabowski.JPGAs in the flower garden, fungal and bacterial pathogens that infect tree leaves, survive the winter on these same leaves once they have fallen to the ground. New fungal spores and bacterial pathogens will be produced in the following spring to infect the newly emerging leaf buds. Other pathogens survive within live branches, the trunk or roots of the tree. Depending on where the pathogen is living, the control strategy is different

Photo 2 (right): Black knot on Prunus. M.Grabowski
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  • Scout trees and shrubs for any signs of infection before the first hard frost. Make notes as to where the pathogen is found. In leaf spot diseases, the pathogen infects the leaves. With cankers or galls, the pathogen survives in the infected branches.
  • After leaf drop, rake up and remove all leaves from trees suffering from any leaf spot diseases. If there are too many leaves to collect, use a mulching lawn mower to chop of the leaves and speed up their breakdown.
  • Infected leaves can be composted, burned (if allowed in your city) or buried.
  • It is also important to help trees prepare themselves for winter by providing adequate water until the ground freezes. The trees root system will continue to take up water even after leaf drop. Research has shown that trees stressed by dry soil conditions are more likely to suffer from frost cracks. For more information about frost cracks visit http://www.extension.umn.edu/yardandgarden/YGLNews/YGLNews-Oct0106.html#frost
  • If the base of the tree is mulched, make sure that the mulch is not piled up against the tree trunk. Volcano mulch cones provide excellent hiding places for rodents in the winter and can result in damage from rodent feeding along the trunk of the tree. Rake any mulch away from the trunk so that an air space occurs between the trunk and the mulch.

Lawns

Thumbnail image for 10-01-09pink and gray_medium_ B.Mugaas.JPGSnow mold is a common disease of Minnesota lawns. Although this disease most commonly causes problems in early spring, there are many cultural control practices that can be implemented now to reduce problems next year. The fungi that cause snow mold love moist cool conditions.

Photo 3 (left): Lawn with pink and gray snow mold  B.Mugaas

  • Reduce mowing height to 2.0 - 2.5 inches. This will allow the turf to remain upright underneath the snow cover. Longer grass flops over creating moist pockets that favor snow mold growth.
  • Remove all leaves from nearby trees and shrubs from the lawn. This can be done by using a mulching lawn mower to break up the leaves or by raking and removing the leaves. Clumps of leaves left on the grass, do not allow the grass leaves to dry properly and create conditions favorable to snow mold.
  • If making a second application of fertilizer, wait until the grass blades have stopped actively growing.  This typically occurs about mid to late October in the Twin Cities. The roots and crowns of the grass plant will still be active and will use the fertilizer nutrients to build up the plant's food reserves. If fertilizer is applied very late in the season,  while the turf is still growing above ground, new leaves may not have time to harden off before winter. This soft succulent tissue is especially susceptible to snow mold.

Components of and Factors Influencing Fall Color

Karl Foord, University of Minnesota Extension Educator

The tree's response to the decreasing day lengths in the fall is to form an abscission layer at the base of each leaf. As this layer forms, it slowly cuts off water and mineral supplies to the leaf and reduces the manufacture of chlorophyll. As chlorophyll supplies decrease, previously masked carotenoid pigments in the leaf become visible. Carotenoid pigments are split into two classes based on oxygen content: xanthophylls and carotenes.   Xanthophylls, which contain oxygen, are yellow. Carotenes, which do not contain oxygen, are orange. Carotenoid pigments absorb light energy like chlorophyll and serve to protect chlorophyll molecules from photo damage. A carotene you may have heard of is β-carotene which is a precursor to vitamin A. In humans, vitamin A is a pigment essential for good vision.

10-1-09_Med_maplesturningcolor_upclose.JPGAnthocyanin pigments are another important component of fall color, contributing reds and purples to the fall palate. These pigments are not present in the leaf during the active growing season, and form in the leaf in the fall. Anthocyanin pigment formation is a function of sunlight, which is why you may see leaves at the tops and southern facing parts of trees turning colors before the rest of the tree.  When the first leaves of the season fall, the remaining leaves receive more light and develop more color. This phenomenon can also be observed in wooded areas where trees on the edge of woods or those that are taller develop color first.  The smaller trees that have been shaded by taller trees will not develop color until sunlight reaches them.

Photo 1 (left): Maple turning fall colors. Note the outer most leaves exposed to the most sunlight are turning first. Karen Jeannette

Anthocyanin pigments are also present in many fruits. For example, if you see an apple that is highly pigmented on one side and not on the other, it may be because the colored side was exposed to light and the other side was shaded by leaves. Many of our favorite fruit species, such as blueberries, cranberries, raspberries, blackberries, cherries, grapes, and eggplant contain anthocyanin pigments.

Functions of superior fall color

One environmental component that does not add to fall color is frost. A severe frost that is premature will kill the leaf cells and not permit the colors to develop. The leaves will instead turn brown, and drop

Superior fall color displays are a function of weather and the condition of the trees. When healthy, pest free plants with sufficient nutrients and water experience bright, sunny, and cool autumn days, and cool but not freezing autumn nights, we are treated to a magnificent display of fall color. Varying weather conditions can influence the timing of fall color. To get an up-to-date fall color report go to the following website. http://www.dnr.state.mn.us/fall_colors/index.html.


The following figure shows the average time "peak" color is obtained in different parts of Minnesota.


Image courtesy Explore Minnesota @ http://www.exploreminnesota.com/

colormap.gif_CRexploremnstateus.gif

Wealth of Education Found in the Display and Trial Garden

Emily Tepe, Research Fellow, Department of Horticultural Science

10-1-09ediblelandscaping_emilytepe.JPGIf you walk through the St. Paul campus Display and Trial Gardens these days you're bound to see a lot of activity. No, I'm not talking about bees on the flowers (although there were a lot of those with the unusual warm weather in September), I'm talking about students. With the start of the fall semester comes a plethora of courses on plant identification, propagation, diseases and insects. The Display and Trial gardens offer a convenient and valuable living laboratory for these courses. In fact, throughout the year (save for a couple of months in the depths of winter) these gardens offer education to many people in the University community and beyond.

Photo 1 (left): Edible landscape portion of the University of Minnesota Display and Trial gardens. Emily Tepe

An Inspiring Outdoor Classroom

The Display and Trial gardens are comprised of various areas between Alderman Hall (home of the Department of Horticultural Science) and the Plant Growth Facilities on Gortner Avenue. Trees, shrubs, and hardscaping create the foundation for the gardens, and break it up into beds, each with their own theme. These themes change from year to year as new varieties are introduced, student projects are realized, and interesting gardening styles bring an opportunity to explore and experiment. The 2009 season brought some inspiring plantings and great educational opportunities.

These educational opportunities often get started while there is still snow on the ground, as students propose projects for the garden and begin designing beds and planting seeds in the greenhouse. Classes ,such as Professor, Neil Anderson's Floriculture Crop Production, research and schedule their assigned crops, working backwards from the planned finish date (mid-May), to assure their annual flowers are at the perfect stage for judging before being planted out in the gardens. Many of the varieties they grow are trials for major seed companies.

When spring arrives, students who have proposed projects for the gardens, begin breaking ground, laying out beds, sowing seeds, and eventually setting out transplants. They are responsible for maintaining their plantings throughout the season, keeping the beds watered, weeded and looking good. It's a great experience for students to take what they've learned in the classroom and put it all into practice. These projects bring the fresh ideas of students to the forefront, allowing them to experiment with new concepts and interesting designs, and even showcase some of their research.

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By the time the gardens are in full swing, the St. Paul campus is pretty quiet. Most of the student body is gone for the summer, and the gardens become an inspirational outdoor venue for summer camps, youth enrichment programs, Master Gardener events, and horticulture industry field days. 

Photo 2 (right): Master Gardeners tour the Edible Landscape at the University of Minnesota State Master Gardener Conference. Emily Tepe

On any given summer day you are bound to find a group of high school students cutting flowers for a design and marketing program, or a flurry of youth in matching t-shirts tending a plot of vegetables; kept on task by their nurturing and enthusiastic mentors. Members of the local community often visit the gardens to view the new varieties released by the University, the vast array of annual flowers, and the creative ideas such as this year's Edible Landscape.

A Living Laboratory

10-1-09PlaPathclass_EmilyTepe.JPGOnce classes start in September, University students begin spending a lot of time in the gardens. Many of the students in the introductory horticulture courses have never seen some of these plants before, and the gardens offer a close-up look at the topics they're studying. Tom Michaels, professor in the Department of Horticultural Science (teaching Plant Propagation this semester) said of the Edible Landscape portion of the gardens, "Students pass right by those beds every time they come to lab. They can't help but see examples of the food they buy in the produce department actually growing in front of them. It gives me the opportunity to talk about those foods and encourage them to stop by the beds and find examples of how chard differs from lettuce or dinosaur kale, or similarities and differences between beans and peas". The gardens are indispensable for the plant identification courses as well. Students find examples of hundreds of species, and with hand lenses and forceps, can scrutinize tiny flower parts to determine the plant family to which they belong.

Photo 3 (above): Plant pathology students observing symptoms of apple scab in the Display and Trial garden. Emily Tepe.

Horticulture students aren't the only ones spending time in the gardens. The Display and Trial Gardens provide a wonderful laboratory for plant pathology and entomology students as well. Todd Burnes, scientist in the Department of Plant Pathology, said numerous courses spend time in the gardens identifying and studying various plant diseases. While in the home garden, powdery mildew, leaf spot and white mold would likely prompt immediate action, here we aren't so hasty. The opportunity for students to observe the symptoms of diseases, collect samples and study them in the lab is worth a few ugly plants here and there at the end of the season. Entomology students roam the gardens, sweeping their longs white nets along the edge of the prairie strip, or carefully trapping unsuspecting insects on the zucchini flowers. Once back in the lab, they'll identify and study their specimens.

Photo 4 (below and right) : Powdery mildew on zinnias in the Display and Trial Gardens. Emily Tepe.10-1-09_Med_powderymildewonZinnia_EmilyTepe.JPG

It is truly amazing the wealth of education that can be found in a garden. Here on the St. Paul campus, the Display and Trial gardens offer many people a chance to get up close and personal with flowers, grasses, trees, fruits and vegetables. And whether in class or just wandering through, there are countless opportunities to discover. Every garden offers such opportunities for young and old alike.
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