CRUCIFERAE MUSTARD FAMILY 
WESTERN WALLFLOWER 
Erysimum asperum DC. 
Orange-yellow is an unusual flower color, not only in the 
Mustard family but among flowers in general. The large bright 
orange-yellow flowers of the Western Wallflower therefore have 
undoubted value in attracting 
certain insects that will ac- 
complish pollination, and they 
make this plant a very con- 
spicuous inhabitant of open 
places and woodland borders. 
It is found only locally from 
Illinois and Ohic to Newfound- 
land but is more common 
westward to Colorado and 
New Mexico. 
‘(Pheistem,; 123 feet ‘tall, is 
slightly rough with short hairs 
and is usually simple but may 
branch near the top. The stem 
leaves may be somewhat 
toothed as shown, or they may 
be entire. Lower leaves are 
somewhat larger and _ they 
taper into short petioles. 
The flowers have the usual 
4 sepals, 4 petals, 6 stamens 
and 1 pistil, and bloom from 
April to July. The pods are 
4-sided and contain 2 rows of 
seeds. 
The Wormseed Mustard, Erysimum cheiranthoides L., blooms 
in July and August along the banks of streams and in the open. It 
is found locally in river bottoms throughout Illinois. The slender 
and branching stem is roughish and the lanceolate leaves are barely 
toothed. The small pods are upright on slender spreading pedicels, 
and are blunt angled. The flowers are the usual Mustard family 
yellow. Treacle Mustard or Tarrify are other names given it in 
various parts of its range, from Newfoundland through New Jersey 
to Missouri and the Pacific coast. 
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