Poison Ivy

Poison Ivy is a perennial woody plant that grows as either a low shrub or a climbing vine. Poison ivy is native to North America and is common in Wisconsin, growing in pastures, roadside ditches, fence rows, wooded forests, beaches and parks. Contact with poison ivy causes skin rashes, blisters and other allergic reactions. Learn identification and control in this factsheet.

Phenology

Karen Delahaut, UW-Madison Fresh Market Vegetable Program Revised:  5/17/2012 Item number:  XHT1085 The word phenology is derived from the Greek word phaino meaning “to show” or “to appear”.  Phenology is a branch of science that studies the relationships between periodic biological events—usually the life cycles of plants and animals—and environmental changes.  Natural events such as […]

Degree Day Calculation

Karen Delahaut, UW-Madison Fresh Market Vegetable Program Revised:  8/6/2012 Item number:  XHT1086 Indicator plants are not always suitable for the timing of pest management practices.  You may not have the critical indicator plant  nearby to time local activities, or there may not be a good indicator plant for a particular pest’s crucial life stage.  Another […]

Wild cucumber invading area with Vijai Pandian (August 26, 2019)

There is a timing for all plants including weeds to be conspicuous at a certain season in natural landscape. In autumn, one such attractive weed that has begun to catch attention in southeast Wisconsin is wild cucumber (echinocystis lobata). Native to Wisconsin, wild cucumber is a fast-growing … Link to full article.

Dodder, Cuscuta spp.

Tangles of pale yellow or bright orange strings running amok over other plants may remind you of science fiction tales, but there are actually real plants that grow like this. The nearly leafless, stringlike stems of dodder can be seen occasionally on a wide variety of plants in different habitats. Learn more about the biology of these parasitic plants that depend on their host plants for nutrition in this article…

Jewelweed, Impatiens capensis

With showy orange flowers, jewelweed comes into its own in late summer and fall. Growing in dense patches in moist, shady habitats, this native plant offers nectar for hummingbirds and other pollinators. Usually grown just as a wild plant, it can be added to rain gardens or to suppress weeds in appropriate areas. Learn more about this self-seeding annual in this article…

Wild Parsnip

Wild parsnip (Pastinaca sativa) is an aggressive Eurasian member of the carrot family that grows in sunny areas and tolerates dry to wet soil types. Very invasive, it can overtake roadsides and fields. Contact with this plant can cause severe skin blisters and permanent scarring. Learn how to identify and control this invasive plant in this factsheet.

Carpetweed, Mollugo verticillata

Carpetweed lives up to its common name by quickly forming a flat mat over the ground. This prostrate summer annual has freely branching stems with whorls of green leaves at the widely spaced nodes. It is most common in disturbed areas – gardens, new or thin lawns, and roadsides. Find out more about this common weed in this article…

Field Pennycress, Thlaspi arvense

There are many weedy plants in the mustard family. It would be easy to overlook field pennycress early in the season, but once the distinctive seed pods develop with a bottle-brush-like appearance, and especially once they start to dry, this plant becomes much more noticeable. Learn more about this introduced weed by reading this article…

Dandelion, Taraxacum officinale

Those cheerful yellow flowers are everywhere in spring. Dandelion is a European species that has made itself at home throughout North America. A menace to gardeners and homeowners looking for a lush, green lawn, this plant can also be cultivated or foraged as food. You can find out more about this ubiquitous weed in this article…

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