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| Landscape Alert newsletter | ||||
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| Vol. 22, No. 6, May 18, 2007 |
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| In this issue Landscape and nursery  Update on garlic mustard biological control Cone season begins Should I boycott cypress mulch? Scouting for diseases: SclerotiniaTurfgrass Frost and grass sawfly European chafer found the in the Upper Peninsula Scouting for weeds: black medic, birdsfoot trefoil and yellow woodsorrelChristmas trees and forestry Armillaria root rot Christmas tree and forestry pest update Gypsy moth spray window datesAround the home Clover mites are swarming in and on homes Insect (and spider) update from Diagnostic ServicesOther news Turn vacant lots into food and profit Weather news |
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| Update on garlic mustard biological control Garlic mustard is a biennial invasive weed native to Europe that is now widely distributed across North America from Georgia to Alaska. In a recent Landscape Alert (Vol. 22, No.2, April 13, 2007), Rebecca Finneran described garlic mustard’s two year life cycle and recommended control strategies for homeowners and land managers (view images). Ongoing research has shown that garlic mustard seeds can remain viable in the soil for at least ten years. Thus, long term management by hand is impossible for all but the smallest infestations. A search for suitable biological control agents for garlic mustard was initiated in 1998 by MSU collaborators at Cornell University, the University of Minnesota, and CABI Bioscience in Switzerland. Efforts are now focused on four beetles (weevils) in the genus Ceutorhynchus, whose larvae target multiple stages in garlic mustard’s life cycle. |
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| Larvae of these species mine inside the root crowns of overwintering rosettes (Ceutorhynchus scrobicollis), mine in garlic mustard stems and leaf petioles (C. alliariae, and C. roberti), or feed on developing garlic mustard seeds (C. constrictus). Adults of all four species feed on garlic mustard foliage, which further reduces seed production. Population modeling studies by MSU researchers Adam Davis (now with USDA ARS in Illinois), Doug Landis and Doug Schemske suggest that releasing the root crown miner either alone or in combination with one of the stem-mining species is likely to be the most effective strategy for the greatest number of invaded sites. Current work in our lab is focusing on refining these models with new data we are collecting from Michigan and Illinois populations of garlic mustard. Before weed biological control agents can be released, researchers must evaluate the breadth of their feeding preferences to demonstrate that they won’t harm non-target plant species. This host specificity testing has been completed for the root crown miner, and a proposal to conduct test releases is currently being prepared for the federal Technical Advisory Group, which oversees weed biocontrol. Testing is continuing on the other three candidate agents in Switzerland, and in a quarantine facility at the University of Minnesota. This means that biocontrol agents will not be available in Michigan for at least another one to two years, if they are approved. Until then, keep pulling garlic mustard to stop it from spreading. For more information on garlic mustard invasions and control in Michigan, please visit http://ipm.msu.edu/garlicmustard.htm and check back for updates throughout the year. More thoughts on managing garlic mustard The goal of management is to prevent garlic mustard from producing new seeds. Most first year seedlings and rosettes will die naturally, so management efforts should be focused on second year plants. Second year plants are easy to distinguish from first year rosettes in late spring once their stems elongate in May and they begin producing white flowers. First year rosettes will not have long stems or flowers and lay close to the ground. In summary, small infestations can be managed with vigilant pulling of second year plants every year prior to seed production or with careful application of glyphosate (e.g. Roundup) during the late fall or winter when most native species are dormant. We now know that viable seeds can develop on any garlic mustard plants that have already flowered, even after the plants have been pulled. For this reason, we no longer recommend burying pulled plants. Plants should be bagged in plastic, tied up, and removed. |
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| Cone season begins We are beginning to receive reports of cones developing in Fraser fir Christmas tree plantations. So far, the indications are the crop is variable, with relatively few cones in some areas and fairly heavy cones in others. Firs are known to exhibit a biennial pattern of cone production. That is, heavy cone crops alternate with light cone crops. The physiological explanation is based on source-sink relations. In heavy cone years, trees allocate their resources to the current year’s cone production, and therefore have less remaining energy to put into new shoot growth and buds for the following year. Based on this, some alert readers may be asking, “Since we had exceptionally heavy coning last year, shouldn’t there be few cones this year?” Part of the answer is that growers usually “short-circuit” the alternate-bearing cycle by picking cones when they are small, and before they become a major drain on the tree’s resources. We will likely see evidence of this if we look at conifers in the landscape, which had heavy cones last year, but were not picked. The other part of the answer is that environmental signals can still override the internal signals within the tree. High temperatures, drought stress and high levels of nutrition promote cone formation the following year. In 2005, June in Michigan was warm, which contributed to heavy coning in 2006. Last year was cooler, but also drier in some areas, which may contribute to this year’s crop. |
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| Should I boycott cypress mulch? It’s hard to think of mulch as a controversial topic, but as with most things these days, we find people on both sides of an issue. As with most things these days, some of the opinions are based on substance, others are not. In the southern United States, some environmental groups are advocating a boycott of cypress mulch. Cypress mulch is derived from baldcypress and pond cypress, which grow in ecologically sensitive wetlands in the Southeast. Cypress wood is highly valued for is natural decay resistance. Florida and Louisiana are the leading states for cypress harvesting for timber and other products. In Louisiana, it is unclear if cypress is logged solely for mulch, but cypress harvesting for mulch does occur in Florida. According to Dr. Jim Chambers, professor of Forestry at Louisiana State University and chair of a governor’s science panel on forested wetlands in Louisiana, cypress mulch production is a sensitive issue. “Many of our cypress-tupelo forests are in a severe state of decline. As you can imagine, these forests are very important to south Louisiana for many reasons. Areas permanently flooded, areas that are flooded for substantial parts of the growing season and areas subjected to salt water input, cannot regenerate. The amount of forested areas with these conditions continues to increase as subsidence increases, coastal wetlands are eroded by storms, and human impacts on hydrology continue to degrade many sites.” The inability to regenerate new stands of cypress is an important concern and calls into question the sustainability of cypress harvesting on these sites. Chambers is working with environmental groups and others to develop a process to certify that mulch is produced from sustainable forest harvest operations. Another issue related to cypress mulch, is a claim that is circulating in parts of Michigan (and perhaps elsewhere) that cypress mulch is linked to cancer. I conducted a search of the National Library of Medicine and National Institutes of Health literature database (www.pubmed.gov) on cypress and cancer. The only hits I found were related to studies looking at falsecypress (Chamacyparis) extracts for anti-cancer properties, similar to taxol. The claims of cypress mulch and cancer may be an amalgam of the environmental concerns over cypress harvesting discussed above, and concerns over use of mulch derived from CCA (chromated copper arsenate) treated wood, which is used for decking and other uses similar to cypress. Research has shown that leachate from mulch containing CCA treated wood can have elevated levels of arsenic and metals above established health standards. |
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| Scouting for diseases: Sclerotinia Pathogen: Sclerotinia sclerotiorum (View images). Hosts Include: Anemone, Aquilegia, Aster, Bellis, Campanula, Coreopsis, Delphinium, Digitalis, Helianthus, Hosta, Iris, Liatris, Lupinus, Papaver, Platycodon, Rudbeckia and Scabiosa. Symptoms: Pre- and postemergent damping-off, crown rot, and blighting of foliage and petioles. Small, hard, irregular, black structures called sclerotia may be present on or in plant tissue (especially inside stem and petiole tissue). White, fluffy growth on affected plant parts is most readily visible in high humidity. Spread: Sclerotia, long-term survival structures, are found in soil and on plant debris. The disease is primarily spread when these structures are moved. Disease can also be spread when infected plant material is moved.Under certain environmental conditions, mushroomlike structures (apothecia) are produced. These release air- borne spores. Management: Field soil should be sterilized before use in growing media. Susceptible crops should not be grown in areas with a history of white mold problems. Additionally, good sanitation is important to limit spread. Control weeds in production areas – some weeds are hosts to S. sclerotiorum. Fungicide drenches can protect plants from infection. |
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| Frost and grass sawfly After the heavy frost across many areas of Michigan last night and into this morning, don’t be surprised if in the next week you observe some leaf tip burning on the turfgrass. The injury looks very similar to injury you might see from a dull mower blade or a liquid fertilizer application during the heat of the summer that can burn the leaf tips. The turf will quickly grow out of this damage, and after the next mowing the damage will be a distant memory (view images). Grass sawfly is making a repeat engagement in the Kalamazoo area as I have had several confirmed sightings from the turf specialists at the Farm N Garden store. Last year, Howard Russell wrote a nice article in the Landscape Alert’s May 19, 2006 issue, describing the grass sawfly. The lawns where the damage is being observed usually have a woodlot border, and the grass sawfly damage is thinning the turf starting near the woods, and then working into the lawn. |
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| European chafer found the in the Upper Peninsula Jim Isleib, MSUE director in Alger County, sent in a sample of white grubs that a homeowner collected from his yard. The grubs were identified as European chafer, Rhizotrogus majalis (Coleoptera: Scarabaeidae). I don’t keep or have official records, but I believe this is the first confirmed report of European chafer in the Upper Peninsula. This bug has been ravaging lawns in the Lower Peninsula for years. European chafer grubs have a very distinctive rastor pattern or arrangement of spines on the inner surface of the tip of the abdomen. (view photos) The extremely cold Upper Pennisula winters apparently have little or no effect on this very cold hardy beetle. |
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| Scouting for weeds: black medic, birdsfoot trefoil and yellow woodsorrel The yellow-flowered, compound-leafed weeds will be blooming in our lawns very soon. The culprits include black medic, birdsfoot trefoil and yellow woodsorrel. These weeds all have small yellow flowers and compound leaves. Just as with any other pest, identification of these yellow-flowered weeds is important to understanding why they are in the lawn. Is the site low in nitrogen? Is the site drought stressed? Are you mowing too low? These could be just a few reasons why black medic, birdsfoot trefoil and yellow woodsorrel are thriving in the lawn. Understanding and addressing the cultural conditions that promote certain weeds in the landscape, will certainly provide more control than any herbicide treatment alone. Improving these cultural conditions in combination with an herbicide treatment can be very effective. Herbicides that have good activity on black medic, birdsfoot trefoil and yellow woodsorrel in the lawn include 2,4-D, dicamba, triclopyr, clopyralid or mixtures of these active ingredients. Black medic: (Medicago lupulina L.) Family: Fabaceae (Legume) Life cycle: Prostrate, trailing summer annual. Leaves: Alternate, compound – with three oval to egg-shaped leaflets – hairless to sparsely hairy, shallowly toothed along the upper half and tipped with a small point. The central leaflet is found on a definite stalk; the two lateral leaflets are nearly stalkless. A pair of stipules is present at the base of each petiole. Stems: Prostrate, trailing to ascending stems are wiry, usually hairy, multibranched from the base and up to 2 feet long. Flowers and fruit: Numerous, very small, yellow flowers are formed in dense, mostly globe-shaped, cloverlike clusters. Fruit are clusters of black, coiled, kidney- to bean-shaped, one-seeded pods. Reproduction: Seeds.
Birdsfoot trefoil: (Lotus corniculatus L.) Family: Fabaceae (Legume) Life cycle: Mat-forming perennial. Leaves: Alternate, compound with five generally oval and smooth-margined leaflets. Each compound leaf has three terminal leaflets and two reduced leaflets near the stem. Stems: Prostrate and spreading to semierect stems are herbaceous, branched from a tough crown and up to 3 feet long. Plants form mats by stolons and rhizomes. Flowers and fruit: Bright yellow, pealike flowers, sometimes streaked with red, are found in flat-topped clusters at the ends of long stalks. Fruit are several linear, cylinder-shaped pods formed in the shape of a bird’s foot. Each capsule contains several roundish, shiny, olive to black seeds. Reproduction: Seeds, stolons and rhizomes.
Yellow woodsorrel: (Oxalis stricta L.) Family: Oxalidaceae (Woodsorrel) Life cycle: Low-growing annual or simple perennial. Leaves: Cotyledons are rounded to oblong. Gray-green leaves are alternate, compound and cloverlike, with three heart-shaped leaflets that attach at the pointed ends. Long-stalked leaves have smooth surfaces, but they are fringed with hair along the margins. Stems: Low-growing, prostrate to erect stems with minimal branching at the base, up to 20 inches tall. Plants spread by long, slender rhizomes. Flowers and fruit: Yellow flowers with five petals are found in long-stalked clusters. Fruit are ridged, hairy, cylinder-shaped capsules with pointed tips that range from 0.5 to 1 inch in length. The capsules explosively eject small seeds with a sticky coating up to several feet away. Seeds are mostly brown, ridged, oval and flattened. Reproduction: Seeds and rhizomes.
Note: Identification information for more weeds is available in the new field guide An IPM Pocket Guide for Weed Identification in Nurseries and Landscapes. To order, call 517-353-6740 or visit: http://www.ipm.msu.edu/pdf/pocketGuidesLandsc07.pdf |
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| Armillaria root rot This past week, I visited a field of small Black Hills spruce where many of the trees had died. Digging up the trees, we noticed swelling and resing at the root collar area. Looking more closely at the larger roots, we found the characteristic white mycelia mats under the bark. Armillaria root rot can be caused by several species of Armillaria, and for diagnosis and management, knowing the species is not that critical. This fungal pathogen attacks several hundred woody species, as well as some herbaceous plants. It is particularly common to forested areas or areas that had been forested. Armillaria exists most of its life as a saprophyte, but it can infect trees that are weakened by stresses. Sometimes it can even infect healthy trees, which are killed outright or are weakened, leaving them vulnerable to other pathogens or environmental stresses. Armillaria produces rhizomorphs, which grow under the bark of dead or dying trees and stumps. In at least one circumstance last year, we were able to trace the rhizomorphs from the dead trees in the plantation to the dead stump of the previous fir crop. Rhizomorphs can grow up to 60 feet advancing less than 10 feet per year. When a rhizomorph comes into contact with a root of a host species, the fungal mycelium adheres to and then penetrates the root by secreting digestive enzymes. The fungus is then able to grow through the root and subsequently up into the trunk. Armillaria can also spread from tree to tree through root grafts. The rhizomorphs may also give rise to the sexual mushroom stage, particularly after wet periods during the fall. These mushrooms release spores that may infect the trees; however, it is unlikely that these spores play a prominent role in the disease cycle. Infected trees exhibit symptoms similar to other root diseases. In otherwise healthy trees, crown symptoms may take several years to develop and may be accompanied by branch and shoot dieback and premature foliage loss. However, in weakened trees, foliage may rapidly turn color with tree death occurring soon after. Because Armillaria is a natural component of the forest ecosystem, it is not possible to try to eradicate the fungus. The best way to control the disease is to prevent trees from becoming stressed. Remove dead trees and the stumps from previous plantings. Avoid planting into cut over sites, especially those with hardwood stumps. In areas where Armillaria has been a problem, do not continue to plant susceptible trees, such as balsam or Fraser fir. Keep trees as healthy and as vigorous as possible. |
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| Christmas tree and forestry pest update Frost damage The freezing temperatures that occurred this past week resulted in frost damage to Douglas-fir, spruce, balsam, corkbark and concolor firs. (view images) Since most of these species had broken bud by that point, the freeze resulted in textbook examples of late frost damage. This damage is characterized by browning or wilting of new shoot growth. While frost damage looks severe when it first occurs, most trees are able to recover. Some trees might need some corrective pruning if damage is especially severe. Pine shoot beetle Just a reminder, if you have pine fields enrolled in the Compliance Program, you need to collect and destroy all trap logs or trap trees by May 20. Be sure you chip or burn trap logs and trap trees, as well as any other pine brood material you might have generated over the last several months. Cooley and eastern spruce gall adelgids on spruce New galls usually appear around 200-300 degree days base 50. Once the new galls are present, insecticides will not be effective. Cooley on Douglas-fir If you had lots of distorted needles from Cooley adelgids on your Douglas-fir trees last summer, you need to be keeping an eye on your trees. Look for the dark-colored nymphs on the new needles. Once buds break, the adelgid eggs will hatch and the nymphs move down to feed on the soft, succulent needles as they expand. These nymphs will be exposed at the ends of the shoots and will not be protected by the little white waxy fibers they secrete. If you need to use an insecticide, this will be the best time to apply it. Time to scout for pine needle scale If you have Scotch pine trees that had high densities of pine needle scale last year and your fields are in southwest or southeastern lower Michigan, you need to be scouting your trees right about now. The first generation of eggs will usually hatch around 300 degree days base 50. It's not necessary to apply an insecticide immediately after you see the reddish-colored crawlers. In fact, it's best to let the crawlers settle down and establish feeding sites on the needles( the hyaline stage – 400-500 GDD Base 50). At this point, the immature scales are exposed and have not yet secreted the white, waxy protective armor. If you can apply your spray at this point and if you get good coverage, you should get good control. Keep in mind that pretty much any registered, contact insecticide will be effective on pine needle scale. You do not need to use a systemic product. This scale feeds on sap from the parenchyma cells in the needle, and systemic insecticides are not going to be more effective than contact insecticides. (In contrast, pine tortoise scale feeds on phloem sap, and systemics are likely to be more effective than contact insecticides). Spruce needleminer On several samples of spruce that came into the office, I found spruce needleminer larvae webbed into nests of hollowed-out needles. These larvae will feed for a few weeks and then pupate. Adults begin to emerge in mid-June and lay eggs on the needles. About two weeks, larvae hatch and begin mining needles. Even though the larvae are present now, they are pretty protected in the webbed nests. Timing to control this insect will be to control the larvae just after they emerge from the eggs, in late June to mid-July. Pine root collar weevils Pine root collar weevil larvae girdle the root collar and roots of Scotch, Austrian, red and eastern white pine. This feeding can weaken and kill trees. Trees attacked by this weevil may fall over and die one to four years after being attacked. Weevils require two years to complete their entire life cycle. Adult weevils lay eggs at the base of pine trees. Each female adult will lay 10 to 70 eggs in one season. Eggs hatch in seven to 17 days, depending on temperature. Larvae are small (up to 1cm long), whitish grubs. Larvae burrow into the inner bark (cambium) of the root collar and large roots, and feed until the weather turns cold in autumn. During the winter, larvae are inactive and are protected from cold temperatures in galleries under the bark or in tunnels in the soil. As the soil warms in the spring, larvae resume feeding. Pupation occurs in chip cocoons made of sawdustlike frass. They are found in the soil near the root collar or, occasionally, under the bark. Adult weevils emerge in 30 to 40 days. Adult weevils should be emerging in the southern part of the Lower Peninsula (300 to 350 GDD50). Use a persistent registered insecticide to drench the root collar of infested trees. Research indicates that this will control parent adults hiding at the base of the tree and newly emerging adults. European pine sawfly Sawfly eggs hatch between 100 and 195 GDD50. This insect rarely builds to high enough levels to significantly damage the health of trees, but we have seen some pockets in past years with large numbers of sawfly larvae causing severe defoliation. Often growers don’t realize they have a problem until they see the trees turn brown from the larval feeding. Make sure to walk through your fields. Scouting through the windshield you can mistake this browning for Lophodermium needlecast on Scotch pine. If you see small numbers of this little green larvae on your pine tree, just clip out the colony. Lots of predators and parasitoids like to attack sawfly larvae too. Douglas-fir needle midge Douglas-fir needle midge is a relatively new pest to Michigan. To date, the only Douglas-fir needle midge we have found are around the Cadillac area. Needle midge adults emerge (around 270 GDD 50) in the spring and live only a couple of days, just long enough to mate and lay eggs. The eggs are deposited in groups on newly expanding buds. Midge eggs hatch in a couple of days, and the larvae immediately bore into young needles. Larvae feed in the needles throughout the summer. When they are full grown in the fall, the larvae drop from the needles and spend the winter in the soil beneath infested trees. To determine when to spray, you need to put out midge traps. Directions for making your own Douglas-fir needle midge trap: http://extension.oregonstate.edu/catalog/pdf/ec/ec1373-e.pdf Check traps ever other day until midges appear. Apply a registered insecticide within a week after first adults are detected. |
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| Gypsy moth spray window dates Growers should note that spray window open dates have now been set for Zone 4 - all compounds and Zone 5 - Dimilin. The following updated chart shows actual and projected open/close dates for application of the two groups of pesticides used for regulatory treatment of gypsy moth in nursery stock and Christmas trees. Since gypsy moth development will vary by location, you will need to monitor development around your farm. Weather conditions will affect caterpillar development and may effect end date of the spray windows. Growers should watch the Landscape CAT Alerts for additional announcements.
* DD = Degree Days at base 50 degrees F. |
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| Clover mites are swarming in and on homes Several folks sent in to Diagnostic Services, clover mites, Bryobia praetiosa (Acarina: Tetranychidae) that they found by the hundreds or thousands on the outside of their homes. (view photos) Many had found their way inside, as well. Clover mites are among the smallest home invaders we have in Michigan. They belong to the spider mite family, Tetranychidae, and as the name implies, they feed on clovers and grasses. People often mistake clover mites for minute six legged insects because their front legs are considerably longer than the others, and they are projected forward giving them the appearance of antennae (as we all know, mites do not have antennae). Lush growing, well-fertilized lawns tend to produce the largest number of clover mites. For whatever reason, newly established lawns also seem to harbor large numbers of clover mites. When conditions are right, clover mites can invade homes by the thousands. This normally happens in the spring, but fall invasions also occur. They are small enough to crawl right through window screens and through cracks around windows, doors and other external openings. If they are crushed during attempts to wipe them up, they can leave tiny red stains. Clover mites are usually a temporary nuisance. They appear suddenly and are generally gone a few days later. Household aerosol insecticides can be used to kill the mites indoors, if deemed necessary, but a soapy rag or wet sponge work just as well on indoor surfaces. A vacuum cleaner equipped with a hose and a soft brush attachment will also work. Wipe or brush carefully to avoid crushing the mites and causing stains. Mites can be removed from the outside of buildings with a garden hose. An insecticidal soap can be concocted by using regular liquid dish-washing soap mixed at the rate of 2 tablespoons per gallon of water. These water-based treatments will not provide any residual control. A more aggressive approach, would be a perimeter treatment of a persistent insecticide along the outside walls and extending about 10 feet out from the foundation. The best long-term method for reducing persistent clover mite invasions, is by providing a grass-free band, 18-24 inches wide, around the house. This can easily be accomplished by open areas of course sand or pea stone, or by installing a plant bed. Removing clovers and other groundcovers from the lawn, may also help prevent mite numbers from building up in lawns. |
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| Insect (and spider) update from Diagnostic Services Paper wasps are busy Paper wasps, Polistes sp., are well into their nest building activities. (view photos) I observed both the European paper wasp, P. dominulus and our native paper wasp, P. fuscatus, on their small newly constructed nests this past week. The European paper wasp is far less selective about where they build their nests. Almost any site that offers the slightest protection from the rain will work for P. dominulus. Inside bird feeders, under or in mailboxes, inside the various nooks and crannies found in parked cars, are among their favorite nesting sites. Controlling paper wasps early in the season is much easier than in August, when the wasps are far less tolerant of those that venture close to their nests. Spiders fight to the death Last Friday evening as I enjoyed my post work beverage of choice, I watched two spiders fight it out in the window of my shop, which my wife occasionally refers to as ”her garage” (Silly!). One of the spiders involved was a big ol’ black jumping spider, known commonly as the Bold Jumping spider, and scientifically as Phidippus audax (Araneae: Salticidae). P. audax is one of the most commonly encountered and (apparently feared) spiders Michigan. The other spider was a type of comb-footed spider that is responsible for many of the cobwebs we find in our homes and outbuildings. Comb-footed spiders belong to the family Theridiidae. The most notorious members of this family are the black widow spiders in the genus Latrodectus. Comb-footed spiders are easily identified by their irregular webs, and their habit of hanging upside down in their webs. (view photos) Jumping spiders are said to be the smartest of all the spiders. They do not spin webs, but rather use their smarts and keen vision to stalk and subdue their prey. My money was on the much larger and more robust Phidippus. I soon learned that I (and Phidippus) had underestimated the power of spider silk. I watched Phidippus move around the edges of the theridiid’s web trying to gain an advantage. After a brief sparing match, the theridiid moved to the center of her web and calmly waited for the Bold Jumper to make her move. The end came quickly for the overly aggressive Phidippus. When she climbed on the web to attack, the theridiid simply out maneuvered her, and surrounded her with strands of silk until Phidippus was trapped. As Phidippus struggled, the theridiid bit and envenomated one of her long front legs she had extended. As the venom did its work, Phidippus quieted, and the theridiid pressed her attack and bit several other of the jumping spider’s legs. When Phidippus stopped moving, the theriviid quickly trussed up her prize in tight wrapping of silk. The fight was over, and the feast was about to begin. I couldn’t help but think about just how geeky I had become. Honorable Mention In closing, I would like to mention a couple of other bugs that came into the lab this past week. Fishflies, Chauldes sp. (Megaloptera: Corydalidae) are out and about. These large and primitive looking aquatic insects are attracted to lights and are commonly found on outside walls of buildings that are near ponds and slow moving streams. See photos of fishflies at: http://bugguide.net/node/view/3610. I also received specimens of male wood roaches, Parcoblatta sp., that a client found in his home. Male wood roaches are also attracted to lights and find their way inside through various points of entry. Wood roaches just visit, they are not known to infested homes like their cousins do. See photos of wood roaches at: http://bugguide.net/node/view/31624 |
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| Turn vacant lots into food and profit Are you interested in reducing urban blight and growing sustainable communities? |
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| Weather news High pressure will hold across the Great Lakes region one more day, bringing a continuation of cooler than normal temperatures Friday, May 18 across Michigan. Another frontal boundary will approach the state from the north Saturday, bringing the chance for showers and a few thundershowers, beginning in northern sections of the state early Saturday spreading southward across the Lower Peninsula Saturday afternoon and evening. After passing southward through the state by early Sunday, the frontal system will stall and eventually begin to creep back northward towards Michigan as a warm front early next week. Some scattered showers and thunderstorms will be possible once again Monday and Tuesday in far northwestern sections of the state, otherwise dry and gradually warmer weather is expected. More widespread showers and thunderstorms are likely statewide as the front passes through the state once again. Temperature wise, highs Friday will warm into the 60's to low 70=s across most of the state. A wide range of daytime temperatures is likely Saturday, with highs ranging from the 50's north behind the cold front to the low and mid 70's south in the warmer air. Nighttime temperatures this weekend are expected to remain in the 30's and 40's across most of the state. Some scattered frost or freezing temperatures are possible again in interior areas of the Upper Peninsula Sunday morning. Warrmer weather is expected over most sections of the state next Monday and Tuesday, with highs returning to the 70's and lows into the 40's and 50's. In the medium range time frame, forecast guidance is suggesting a relatively flat, west to east upper air pattern during the 6-10 day period with the gradual formation a troughing feature across eastern North America by the 8-14 day period. The official NOAA 6‑10 day outlook for May 23-27, calls for a wide range of mean temperatures across the state from below normal levels across western sections of Upper Michigan to above normal levels in the southeastern Lower Peninsula. Above normal precipitation levels are forecast statewide. For the 8-14 day period (covering May 25-31), the outlook calls for temperatures to fall back to below normal levels and for near normal precipitation totals statewide. |
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