Amaranthus

[Greg Shaner]

A colleague of  mine, Lee Schweitzer, is developing a CD Rom to help identify
weeds in the seedling stage. This includes a lot of photographs.  In preparing
information about Amaranthus rudis Sauer and A. tuberculatus (Moq.) Sauer, he
has noted that the leaf veins on A. tuberculatus tend to be arcuate, whereas
the veins on A. rudis extend directly out to the leaf margin.  We have not
been able to find any reference to this difference in various floras we  have
consulted.  Our small herbarium has no specimens of either species.  Has
anyone else noted this difference in leaf venation?  If the trait it
consistent, it would be useful for helping to distinguish the two species.

Regards,
Greg Shaner
Dept of Botany and Plant Pathology
Purdue University
1155 Lilly Hall
West Lafayette, IN 47907-1155
shaner at btny.purdue.edu