Yard & Garden Line News Volume 3 Number 17                                                               November 1, 2001

Features this issue: Spice up Your Winter Landscape with Smart Choices Next Spring Insect Museum: A Hidden Gem, Order Insecta Mystery Disease of Colorado Blue Spruce What's Biting Me? Editorial Notes

Spice up Your Winter Landscape with Smart Choices Next Spring
Deborah Brown, Extension Horticulturist

Bittersweet. Photo credit: Beth Jarvis

When you go to a nursery or garden center to choose a tree or shrub, you usually have a very specific location in mind for it. You also have some idea of how tall you'd like the plant to grow, and maybe even how wide. You might have a special preference for plants with colorful flowers in spring, or ones that go out with a blaze of glory most autumns.

One factor that is all too frequently overlooked is how the plant will look in winter. That's an unfortunate oversight. After all, this is Minnesota. Mid-November is already a dreary time in the landscape, with no relief in sight -- unless you count snow -- for five months or more.

Actually, there are many wonderful trees and shrubs that can add spice to our winter landscape -- and look good during the growing season, too. Some are interesting because of their bark texture or the "architecture" of their branching; others, because their color provides welcome relief.

While plants that drop their fruit in August or September belong in the unpopular "messy" category, trees and shrubs that hang onto their fruits and berries through winter are stars in the landscape. They do double duty, contributing color AND attracting birds and small animals to our yards. We can enjoy watching these creatures as they feed outside our windows, secure in the knowledge that we are helping them survive the winter.

If you live in a newly developed area, or your yard simply needs more trees and shrubs, scope out established landscape plants this winter. A drive through any older, attractive neighborhood will give you ideas of which plants look good. A visit to the Minnesota Landscape Arboretum will yield even more information, because their trees and shrubs are labeled. By spring planting time you'll have a better idea of what will work in your own home landscape.

Of course, you have to choose plants that will thrive where you live. Cold-hardiness, the need for sunlight versus shade, soil type and drainage conditions all must be compatible for plants to succeed.

Conifers

Frosted arborvita. Photo credit: Beth Jarvis

In thinking about winter interest, the first plants that come to mind are conifers, always popular because they remind us of woodlands and idyllic camping trips "up north." And even though most people tend to lump these trees and shrubs together as "evergreens" there is really a wide diversity among them in terms of color, form, needle length and ultimate size.

A word of caution regarding conifers: You must learn how large they're likely to grow before deciding where to site them in your landscape. It's difficult to visualize that shapely little pine in a five gallon container growing eventually to a height of seventy feet or more, thirty-five or forty feet across!

Flowering Crabapples and Relatives
There are many flowering crabapple trees available that bloom beautifully in spring, then develop fruit that persists into winter. Look for the following cultivars, but be sure to check that they are rated hardy for your climate zone. All are good in zone 4, but not all are hardy in zone 3.

'Adams'	'Candied Apple'	'Centurion'
'Flame'	'David'	'Donald Wyman'
'Harvest Gold'	'Kelsey'	'Pink Spires'
'Prairifire'	'Professor Sprengor'	'Profusion'
'Radiant'	'Red Jewel'	'Red Splendor'
'Selkirk'	'Sugar Tyme'	zumi 'Calocarpa'

Mountain Ash trees, like flowering crabapples, are members of the rose family. They, too, produce small, colorful fruit that birds enjoy. In fact, they're usually stripped of fruit by early winter. Sorbus aucuparia, European Mountain Ash, is most readily available at nurseries, but you might also find Sorbus decora, Showy Mountain Ash, a smaller tree with brilliant red berries that's native to northern Minnesota.

Rugosa roses, winter hardy throughout the state, can produce red-orange fruits called rose hips. For hips to develop, though, you must not deadhead or remove the roses as they fade. The ovary of each blossom expands to become the fruit -- provided the flower was pollinated. (The way bees buzz around my rugosa roses, that has never been a problem!)

Other Plants That Hold Their Fruit

Cranberry with fruit. Photo credit: Beth Jarvis

In addition to roses, there are several shrubs that hold onto showy fruit in winter. Perhaps the most spectacular is our deciduous holly, Ilex verticillata, or Winterberry. It's truly a sight to behold, its stems almost obscured by small, brilliant scarlet berries. Until birds devour all the fruit, these shrubs are gorgeous.

Note that each winterberry shrub produces either male or female flowers. You must plant both sexes in order to get fruit, though it's not necessary to have a male shrub for each female.

European Highbush Cranberry, Viburnum opulus, and our native Highbush Cranberry, Viburnum trilobum, both produce clusters of red berries that hang on through most of winter. The sight of those red berries capped with snow is really very lovely.

Bittersweet, Celastrus scandens, is prized each autumn for its stems of vibrant red-orange berries that keep well when displayed indoors. If you don't cut them for dried bouquets, they'll add their beautiful color to the winter landscape, until birds eat them. Like winterberry, you must plant several to be assured of having both male and female plants.

Shade Trees

Corktree bark. Photo credit: Beth Jarvis

River birch, Betula nigra, tops my list of shade trees for winter interest. Like the more commonly grown paper birch, they're often planted in clumps with several stems. But unlike the paper birch, their bark – at least until the trees very large – is very curly with cinnamon-colored highlights, rather than plain white. As an added bonus, you'll find that bronze birch borers are far less likely to damage river birch than paper birch.

Another favorite, bur oak, Quercus macrocarpa, has a distinctly sculptural form, with strong, thick, rather horizontal branches. Because it must be transplanted while still quite young, this particular tree is somewhat difficult to find in nurseries. But it can be ordered. And if all else fails, you can plant your own by collecting acorns from a mature specimen. Squirrels plant them all the time; it would make a great family project.

And finally, there's Sakhalin Cork Tree, Phellodendron sachalinense, prized for its unusual bark which is both fissured and divided into "plates." While not colorful, it certainly provides interesting texture compared to more commonly grown specimens.

Insect Museum: A Hidden Gem, the Order Insecta
Beth Jarvis, Project Coordinator, Yard & Garden Line

Madagascar hissing cockroachs. Photo credit: Beth Jarvis

There's a row of aquariums along a wall in the University of Minnesota's Insect Museum preparation room. Denizens include a Mexican Black Velvet tarantula, a scorpion, a Chilean Common tarantula, another tarantula whose name I missed, and a whole mess of Madagascar hissing cockroaches.

These medium to dark brown cockroaches hide out in a crumpled cardboard edifice. Unlike the German brown cockroaches we know, these are several inches long, about an inch wide and have flat, overlapping body plating that makes them distinct. So distinct, that they've appeared on the X-Files (and undoubtedly other tv shows) when creepy critters are needed. When they get their dander up, they hiss. But they're basically docile, making them great for Entomological show and tells.

In another tank, seven-inch long, inky-black African millepedes, as thick as your little finger with dense ruffles of eyelash-like legs, munch the seeds of half a cucumber.

And these aren't even the insects!

Museum scene. Photo credit: Beth Jarvis

Started in the 1879, the Insect Museum is currently located in the Entomology Department in Hodson Hall on the St. Paul campus. It's the 8th largest university affiliated collection in North America. Due to its research focus, it receives significant funding from the Agricultural Experiment Station. Several Entomology faculty members share responsibilities for portions of the museum collection with Dr. Phil Clausen, curator.

Clausen has been curator of this hidden gem since 1968. He oversees a collection of slightly over 3 million specimens, mostly insects, plus some miscellaneous arthropods such as mites, ticks, spiders, millepedes and scorpions "because no one else wants them, I guess."

Most, if not all of the true insects in the collection are dead. They're found pinned and tagged in display boxes. In some cases, rows upon rows of the same insect species. You can find lists of them at the museum's website at: http://www.entomology.umn.edu/museum/

The collection's insects come from diverse sources. Most of the specimens come from collecting trips but many others come from faculty and graduate student research projects.

Some of the insects collected in Venezuela. Photo credit: Beth Jarvis

There are over 47,000 identified species in the collection but there are a lot of unidentified species as well. Clausen speculates that if every species were properly identified, there would be 90,000-100,000 species in the collection. New insect species are usually identified by scientists studying collection samples, The keying out and comparison necessary to recognize new species can't be done in the field.

This "library of insect fauna" as Clausen calls it, provides comparative samples for entomological researchers all over the world. Samples are shared with or loaned to other institutions of learning, agencies and museums.

Right now, there are between 750,000 to a million insect species world wide. Annually, researchers identify 7,000-8,000 more.

Pinned insects, ready to be filed away. Photo credit: Beth Jarvis

Every year, 50 to 70 tour groups ooh and aah when Clausen pulls open wide drawers in the museum to reveal brilliantly colored butterflies or moths (order: Lepidoptera). Other drawers contain beetles (order: Coleoptera) of all imaginable shapes and sizes, some are gem-like proof that the Lepidoptera aren't the only beautiful members of the class Insecta.

(You may recall scientific classification, from most general to most specific is: kingdom, phylum, class, order, family, genus, species. The memory clue is: kings play chess on Friday, general speaking.)

The tour groups are mostly elementary school kids because "people seem to think bugs are for kids" Clausen mused. But some of the museum visitors include high school students, U of M biology colloquium students or those on a field trip for another class or even students from small colleges.

Sometimes bits of the collection go visiting. Clausen brought a sampler from the collection to the recent Homecoming breakfast and another part is on display at the Bell Museum of Natural History's in their "Oddities & Curiosities of Nature" display. He feels the collection should be more visible.

Collecting trips

Clausen & some African butterflies. Photo credit: Beth Jarvis

Clausen has made 14 collection trips over the years though he wonders if his trip last July may be his last given new luggage restrictions on airlines. Central and South America are popular with collectors because airfare is relatively cheap.

Whenever insects from the collection are photographed for commercial purposes, a fee is collected and saved to fund future collection trips as are the fees charged for insect identifications made for corporations and other organizations.

Collecting groups vary in size, from two or three to over a dozen people. Some participants are academic but others are dealers or amateurs. The amateurs, Clausen noted, are generally after big things–butterflies, moths, etc. Some collect everything. He recalled seeing someone wearing a t-shirt featuring a cartoon of a man with a sweep net and the motto "If it flies, it dies."

Trips may be arranged by a travel agent who specializes in such trips, or through an informal network of referrals by fellow collectors. If a collecting trip is organized for research purposes, a governmental agency or museum from the hosting country may participate or at least assist with accommodations.

Collectors may be required to obtain collecting and or exporting permits. There are no standard permits and requirements vary by country. Clausen chuckled as he recalled his last trip to Cameroon where they were issued a modified big game permit to collect insects; it was the only permit the country had. Permits may restrict collecting to certain families of insects or give the collector carte blanche. Clausen rolled his eyes at memories of countries that demanded detailed lists of all samples collected. But, he doesn't feel permits are a negative thing, necessarily, as they help prove to US officials that collected specimens were legally taken.

There are no quarantine restrictions on bringing dead insects into the US. Samples are preserved in alcohol or fresh samples are put in envelopes and stored in Tupperware boxes, with a preservative to prevent rot and mold growth. Without refrigeration, keeping collected samples fresh for more than 2 weeks is difficult.

Big bugs have little bugs
When you walk into the Insect Museum, the first thing you notice is the scent of mothballs. Mothballs are a deterrent to the dermestid beetle and a few other insects that feed on the mortal remains in cabinets. The beetles, etc. are just doing what comes naturally--recycling..

But it does bring to mind the poem by Jonathan Swift:

Big bugs have little bugs
Upon their backs to bite them.
Little bugs have littler bugs.
And so, ad infinitum.

Mystery Disease of Colorado Blue Spruce
Janna Beckerman, Extension Plant Pathologist

Small black fruiting bodies turned out to be Sirococcus Photo credit: Janna Beckerman

The signs and symptoms looked like Sirococcus, but these fruiting bodies were Leptosphaeria. Photo credit: Janna Beckerman

A fungus pretending to be Rhizosphaera! Photo credit: Janna Beckerman

We've recently received numerous samples of Colorado blue spruce in at the clinic from all over the state. This is not an uncommon occurrence, as this is also the time for fall needle drop. To distinguish between normal fall needle drop and disease, examine where needle drop is occurring. New growth should not be affected.

However, the samples we've received in the clinic are not normal fall needle drop. In Minnesota, Colorado blue spruce grows fast, lives hard and dies young, at the ripe old age of 30 or so. For this reason, blue spruce is not recommended as an urban tree. Common contributing factors in blue spruce death are two diseases: Rhizosphaera and Cytospora. However, the blue spruce samples that we've received this year often have multiple disease disorders in addition to Rhizosphaera and Cytospora! To make matters ever more difficult to diagnose, several new potential disease problems have been reported or observed.

The first of the new disease problems is the mystery disease of blue spruce found in Wisconsin. It has also been reported on black and white spruce. Needle drop, needle chlorosis and shoot blight are symptoms and it has been reported throughout the state. Wisconsin plant pathologists have tentatively identified the causal agent as Dothiora-like, with the black fruiting bodies appearing on the shoots of infected plants. However, recent investigations by the USDA determined that the fungus was not Dothiora.

In Minnesota, we've seen a similar phenomenon on our blue and white spruce. However, the fungi have been identified as Leptosphaeria spp. and Sirococcus. Sirococcus is a well known pathogen of blue and white spruce, and only causes severe infestations during extremely wet springs, like we had this year. Symptoms include needle chlorosis and loss, with numerous black fruiting bodies appearing on the previous years growth. This disease exploded this spring, was not seen from July through September, and just reappeared on a severely stressed blue spruce.

Sirococcus-like symptoms were found in association with the Leptosphaeria-like fungus this spring. Microscopic identification was necessary to differentiate between these two organisms. Symptoms included needle loss, with a characteristic twisting of the needles. This twisting resembled herbicide damage.

The disease Rhizosphaera needle cast frequently infects Colorado blue spruce. Rhizosphaera needle cast is a fungal disease that infects the current year's needles. These needles later turn purple to brown and fall from the tree prematurely, leaving the inner portion of the branch bare. As the disease progresses, severely infected branches die, leaving the tree with a hollow or thin appearance. The disease starts near the base of the tree where humidity levels are the highest, but continues to spread upward. As the disease continues, trees become unsightly and lose their value as a visual screen or privacy fence. The Rhizosphaera pathogen, however, sporulates in the spring. This fall we've observed 4 samples that appear to have Rhizosphaera, but microscopic examination demonstrated that a different fungus was found associated with the needles. This fungus emerged out of the stomates, like Rhizosphaera, but produced brown colored spores instead of the clear colored spores that Rhizosphaera produces. We have not yet identified this fungus.

Since Colorado blue spruce is not native to Minnesota, it often suffers from environmental stresses such as drought, excessive heat, and compacted soils. Spider mites were seen in association with almost all samples we've received. Apparently, Colorado blue spruce is more vulnerable to infection and more severely affected than native white and Norway spruce to some native fungi. To minimize future problems, make sure your blue spruce are well watered and mulched going into this winter. It may be the difference between a healthy spruce and one that should be pruned at ground level!

Test your diagnostic savvy monthly with Disease Watch at: http://www.extension.umn.edu/projects/yardandgarden/PlantPathWeb/Plpa.htm

What's Biting Me?
Jeff Hahn, Assistant Extension Entomologist

Female and male blacklegged ticks. Photo credit: Jeff Hahn

There are several insects and related arthropods that may bite people. This article does not attempt to discuss all of the possible cases but does examine some recent instances to give an idea of some of the variety of reports by people that are (or think they are) being bitten.

When fall arrives, people assume that ticks have hibernated. In fact, blacklegged ticks, Ixodes scapularis (formerly known as deer ticks) can be active down to 39 degrees F. We received several adult female blacklegged tick samples in October confirming that they are still active. Not all ticks found during fall are blacklegged ticks. Have an expert identify any that you suspect are blacklegged ticks.

Blacklegged ticks are medically important because they are a potential vector of Lyme disease. However, finding a blacklegged tick does not automatically mean you have contracted it. Not all blacklegged ticks harbor the Lyme disease spirochaete. For those that do, they need to be biting (head imbedded into the skin) for at least 48 - 72 hours to vector the disease. Symptoms at the onset of Lyme disease can include but are not limited to a red skin lesion with a clear center, malaise, fatigue, chills, fever, headache, myalgia (muscle pain), sore throat, nausea, or vomiting. Arthritis can develop several days to a month later. If you think you may have contracted Lyme disease, consult a physician.

Head lice are an ongoing concern during the school year. Although they are usually associated with children, adults may also become infested with head lice. Before starting a head lice control program, it is critical to determine whether live head lice are present. With this in mind, we received an insect sample that was found on an adult's head that was suspected to be a head louse.

Booklice. Photo credit: Ken Gray Collection, Oregon State Univ.

The sample contained a real insect but it turned out to be a psocid, also known as a barklouse or booklouse. Don't let the name fool you, these insects can not bite people and are harmless to us. Some species are found on tree bark, plant foliage, or under stones, feeding on fungi, lichen, pollen, decaying plants, and other organic material. Other species are found inside buildings preferring to eat molds, fungi, grains, insect fragments, and other starchy material, including glue from book bindings.

It would be very unusual to find a psocid in a person's hair. However it occurred, it undoubtedly was an atypical event. No specific action needs to be taken to control psocids found on someone. Psocids would be expected to go away on their own. Once the insects were correctly identified, then the patient was no longer considered for treatment with head lice products.

In another case, a person was concerned about flea bites. Fleas may be present in homes with or without pests and have a tendency to be more common during fall. However, we found no insects in the submitted sample. It is possible that small numbers of fleas are present in a home but not easily seen. Fleas generally bite around the ankles and legs but it is difficult to identify a problem based just on the bites. If fleas are suspected, there are several methods to detect their presence.

Cat fleas feeding. Photo credit: Nancy Hinkle

The easiest is the white socks test. Wearing a pair of white socks, someone walks slowly across rooms where are fleas are suspected. Fleas are attracted to the vibrations from the walking and the warmth of the person and will jump towards the ankle. Their dark colored bodies show up plainly against the white background of the socks. Another method for monitoring for fleas is to place a shallow pan of water in a room where they are suspected and put an Alka Seltzer tablet into it. The carbon dioxide that is given off attracts fleas. Put a couple drops of dish soap into the water to help prevent fleas from jumping back out of the pan.

Professional pest control services also have an access to a pulsating green light trap which is highly attractive to fleas. These traps are not meant to control fleas but to help determine if fleas are present. If fleas are found, veterinarians have a variety of excellent products to treat pets to control fleas which also eliminates a flea problem in a home. You may also wish to contact a professional pest control service.

However, if fleas or other biting insects are not found, do not treat your home. It is possible that the cause of insect-like bites or irritations is something unrelated to insects or related creatures. This can be harder to diagnose and it may be necessary to consult with a physician. Some other possibilities that can cause similar symptoms include dry air, allergic reaction to personal or household products (e.g., detergents, soaps, cosmetics, clothes, jewelry), environmental contaminants, microscopic fibers (e.g. insulation or paper fibers), certain health conditions (e.g. diabetes, neurological, liver, or kidney disorders), or stress.

Get the low down on this month's insect pests at Insects http://www.extension.umn.edu/projects/yardandgarden/EntWeb/Ent.htm
Editorial Notes

Zinnias, ageratum and black-eyed Susans. Photo credit: Beth Jarvis

This picture was taken this summer during a garden tour, in a private garden. It cheers me just to look at it as we begin to hunker down, in anticipation of a somewhat "normal" winter, whatever that it.

Now that the perennials have been clipped back, bulbs planted, annual and veg gardens stripped bare, gutters cleaned, leaves raked, etc. we can turn toward indoor chores. My list grows as long as a winter's night.

In future issues, Nadilia Gomez, a floriculture grad student, will share the findings of the U's annual flower trials to help you pick winners for next year. Doug Foulk will discuss pear varieties suitbable for Minnesota gardens. We'll be featuring the Southern Research and Outreach Center in Waseca this winter. And we'll look at the Lyme disease research that's done here. Plus much more.

Please feel free to cut and paste any of the articles for use in your own newsletters. All we ask is that you give our authors credit.

Back issues Yard & Garden Line News are on the Yard & Garden Line home page at www.extension.umn.edu/yardandgarden/. Our home page has clickable links to most of the components of the Yard & Garden Line, such as Bell Museum of Natural History, INFO U and the Soil Testing Lab.

Deb Brown answers gardening questions on Minnesota Public Radio's (MPR) "Midmorning" program on the first Thursday of every month at 10 a.m. Katherine Lanpher hosts the program that is broadcast on KNOW 91.1 FM, and available state-wide on the MPR news radio stations.

The 2002 Minnesota Gardening Calendar can be purchases using a credit card on-line at http://www.extension.umn.edu/distribution/horticulture/DG7551.html or by calling Extension's distribution center, 612-624-4900 in the Metro or 1-800-876-8636 in greater Minnesota.

If you have gardening questions, please call the Yard & Garden Line at (612) 624-4771.

If you would like to receive an e-mail reminder when the next issue of the Yard & Garden Line News is posted to the web, just send an e-mail to: listserv@lists.umn.edu (note: the second E in listserve is omitted), leave the subject line blank, then in the body of the message, type: sub yglnewslist
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Happy gardening!

Beth Jarvis
Yard & Garden Line Project Coordinator


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