Wild Cucumber (Echinocystis lobata)

Description
The wild cucumber is an annual plant; that is, it grows from seed each spring and dies in the fall. It produces no woody tissue. It is a climbing vine and has long twisted tendrils which entwine the leaves, stems or branches of other plants. It is usually found sprawling over the low branches of trees or shrubs next to waterways, but can grow as a dense mat on open ground, as well. The leaves, up to 14 cm across, are thin, light green in colour, with 3-7 (usually 3 or 5) large pointed lobes; essentially a "maple-leaf" shape, as in, on our penny (except those are gone now!), not our Manitoba maple leaf. Its male flowers, more conspicuous than the small female flowers, are greenish-white with 6 petals. They bloom in late July and into August. The characteristic "cucumbers", up to 6 cm long, green in colour and covered in soft bristles, form by late August or into early September. They are a form of fruit called a "pepo", a large fleshy berry with a thick skin.

Name
Wild Cucumber (Echinocystis lobata) is a member of the cucumber or gourd family, the Cucurbitaceae. Included in this family are such familiar plants as domestic cucumbers (Cucumis sativus), squashes and pumpkins (Genus: Cucurbita), and other melons (Genus: Cucumis). Its most usual common name is drawn from the resemblance of its fruit to that of the domestic cucumber. Balsam-apple is another common name for Wild Cucumber. It's scientific name breaks down as follows:

Echinocystis:
Echino - from the Greek "echinos", a hedge-hog; the prefix "echin-" always means spiky, prickly or "hedge-hog-like". Cystis is also Greek, referring to a bladder or pouch. So, Echinocystis refers to a spiky bladder, an apt and logical reference to the wild cucumber.
lobata:
From the Greek, "lobos" - a lobe, capsule or pod. This may also refer to the large cucumbers, that are the most significant feature of this plant or it may be referring to the distinctly lobed internal structure of the cucumbers.

Habitat and Range
The habitat of Wild Cucumbers is quite variable, but they are most often found where water is readily available. Waterways that experience spring flooding, which provides both moisture and fresh deposits of silt, along with thick shrubs or trees to grow upon, seems to be ideal habitat for Wild Cucumbers. However, being annuals, they will grow wherever they get a chance. While the large seeds tend to fall to the ground below the parent plants, they could be carried around or cached by birds or mammals and, if uneaten, could end up growing in odd locations.

This species occurs across southern Canada and southward throughout most of the United. It is very common in southern Manitoba, but likely doesn't extend into the boreal forest region.

Life Cycle
Seeds of Wild Cucumber germinate in the spring and the young vines grow rapidly. The vines reach toward the sunlight, using the stems and branches of other plants as supports. The flowers of wild cucumber are unisexual; that is, there are separate male and female flowers at different locations on each plant. As the male and female flowers are found on each individual plant it is still considered to be monecious ("in the same house"). The male flowers are held in small panicles (a panicle is a branched cluster of flowers) and the much smaller female flowers are located in the leaf axils (where the leave stalk, or petiole, meets the stem). Wild Cucumber flowers are in bloom in early to mid-August. The cucumbers, which nearly always contain 4 large seeds (1-1.5 cm long), develop from the female flowers by the end of August and into September. By the time the cucumbers are ripe the entire plant is beginning to die. The cucumbers are the last part of the plant to dry out and die. They open at the bottom, and the large seeds fall out onto the ground, where they will lie until the following spring. By growing towards the light on shrubs and trees along waterways the wild cucumber keeps dropping its seeds in the most advantageous spot for next year's plants to start off. A single plant may grow 20 m or more from where its originating seed first germinated, so its progeny can spread quite a distance over several generations.
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