Owl's Clover

Plant of the Month

Removing invasive plants and weeds is a large part of the restoration work that takes place in our preserves. This can be challenging, since some invasive species look similar to California natives. Help us protect native plants: become a community scientist and record your observations in the free iNaturalist app. This information helps us monitor the open space lands and identify areas of concern.

Please do not pull any plants on Midpen lands; we follow a strategic plan when dealing with invasive species and removing plants can actually spread the growth of unwanted species.

Native plant and their nonnative look-alikes. Can you tell the difference?

    March 2022

    Native - Poison oak (Toxicodendron diversilobum)

    Native PLant of the Month: Poison Oak (March)
    • A deciduous native vine or shrub
    • Found in clearings, forest and fields on ground, climbing and/or hanging down from trees
    • Woody stems with a pinkish shade grow from a foot high and many feet long, which are bare in winter
    • Sprout clusters of three lobed shiny/oily leaves, which are green spring and summer, turning orange and red in autumn
    • Blooms March through June with clusters of white/green flowers that fruit with velvety white berries called drupes
    • Leaves of three, let it be! Every part of this plant is coated in a oily poison and allergen called “Urushiol” (pronounced “yoo-ROO-she-ol”) at all times of the year. Urushiol oil can stay active on dead plants, clothing or objects for up to 5 years and causes contact dermatitis, which may include localized irritation from a rash, itching, burning skin, swelling and/or blistering, in most people.

    Nonnative - English Ivy (Hedera helix)

    Nonnative Plant of the Month: English Ivy (March)
    • Invasive, nonnative, evergreen vine or shrub from the British Isles, northern Europe west to the Caucasus Mountains and Mediterranean region that was introduced as an ornamental planting by early European colonists
    • It has also been planted historically to control soil erosion in many parts of the US
    • Found in many habitats
    • Vines grow with deep-green, glossy, leathery leaves that tend to have lighter-colored veins and three to five lobes, whereas shrub leaves tend to be more ovate than lobed.
    • Shrubs produce clusters of white flowers in the fall and dark blue or purple drupes in the winter; whereas vines do not flower or fruit
    • Alters natural succession patterns in forests by inhibiting regeneration of native understory plants, including wildflowers, shrubs and trees and, as a result, replaces species that native wildlife rely on
    • Both berries and leaves are toxic, and the plant's sap can cause dermatitis in some people



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