Sida spinosa aka Spiny Sida

Sida spinosa belongs to the mallow family, Malvaceae. Its common names include prickly sida, false mallow, and wireweed. Kew places its native range across the tropics and subtropics. NC State lists origins in North, Central, and South America. It is not native to Britain or Ireland. It grows as a summer annual or herbaceous perennial.

The plant grows fast and has an upright, coarse form. Fine white hairs cover its round, green stems. The stems have no scent. A shallow taproot branches into smaller roots below the soil. Green, simple leaves grow in an alternate pattern. Their shapes range from heart-shaped to narrow, oval, or oblong. The edges have rounded or pointed teeth. Leaf lengths reach about 0.25 feet (0.076 metres). Some lower leaf stalks have a blunt green spine beneath them. These spines help distinguish the plant from similar weeds.

Small flowers grow where the leaves meet the stems. Their short stalks can leave them hidden among the leaves. Each flower spans about 0.03 feet (0.008 metres). Pale yellow or light orange petals open on sunny mornings. NC State also lists white among the flower colours. Bloom runs through summer and fall. A column of stamens surrounds the style, a mallow family trait. Round, reddish-brown seedpods follow the flowers in summer and fall. Each pod splits into five sections, each holding one seed.

This plant grows in fields, pastures, roadsides, and railway margins. It also occurs in open woods and beside waterways. It accepts full sun or partial shade. Sand, loam, and clay all suit it. It tolerates acid, neutral, and alkaline soils. NC State lists moist soils, good drainage, and brief wet periods. Its tags also note drought tolerance. The same source lists USDA zones 5–10 and low maintenance. Kew links the species with seasonally dry tropical climates.

Its main landscape drawback is its spread as a weed. It can trouble crops, pastures, and other disturbed ground. Seeds sprout fast, and self-sowing can create groups of plants. Removing spent blooms can help limit this spread. Animals feeding on the leaves can also move seeds. Bees, butterflies, and birds visit the plant. Some mammals eat its leaves, giving it wildlife food value. The supplied sources give no human food or toxicity guidance. They identify no specific insect pest or disease.