povertyweed
Family
AsteraceaeScientific Name
Iva axillarisOther Common Names:
Iva poverty weed
poverty weed
smallflowered marshelder
mouseear pvertyweed
poverty sumpweed
lesser marshelder
Habit
A foul smelling plant poverty-weed forms large colonies in extremely alkaline areas. The cork-like roots can reach depths of 1.8 m. Stems reach around 60 cm tall but are rarely branched. In its ideal environment this species is capable of growing to over 18 m in diameter. Poverty-weed seedlings are a novelty in nature due to the low germination of it's rarely produced seeds.
Leaves
0.5 to 4 cm long and 1 cm wide the leaves covered with rough hair are oblong and pale green. Leaves are thick and stalkless with 1-3 prominent veins at the base. Upper leaves are alternate in arrangement but lower leaves are opposite.
Identifying Characteristics
Nodding flower heads, less than 5mm across are found in the leaf axils, lower leaves opposite with upper leaves in an alternate arrangement. Rarely spreads by seed, primarily propagates its self by budding on its creeping root system. The huge volume of pollen produced by this plant may contribute to hay fever.
Flower Seed Head
Wind pollinated the nodding flower heads produce vast amounts of pollen. They are found as solitary heads in the leaf axils. Most heads measure less than 5 mm across and are composed of greenish disk florets. Floral bracts are united in a 4 to 5 lobed cup.
Seed Fruit
Achenes arise from the female florets bearing 2.6 to 3mm long and 1.6 to 2.2 mm wide seeds. The egg-shaped seeds are reddish-brown to black dull and scaly. This plant rarely produces seed.
Where Found
Throughout western Canada and the United States it can sometimes be problematic in cultivated crops. Poverty-weed is most often found in pastures, railways, waste areas, and road-sides.
Life Cycle
perennial
Plant Type
Herb