Hi Gang, We've had some very fun and useful discussions in this forum about taxonomy, species, subspecies, varieties, and how to distinguish between all the possibilities. Bulbs are sometimes just as confusing as any other plants, and because they may come from far away, or be garden hybrids, bulbs can be very mystifying to some of us as taxonomic entities. I was reading a book recently that had a nice map of the distribution of redbud in Texas (Cercis canadensis). This tree is generally accepted to be represented by 3 varieties in Texas (var. canadensis, var. texensis, and var. mexicana). I colored a map of Texas to reproduce the data in the book (Field Guide to Trees of Texas, B. Simpson, 1999). His map shows the 3 varieties and how they are distributed over Texas counties. Additionally, the book depicts two hybrid swams and the counties where they occur. The hybrid swarms are populations of plants that are intermediate, the plants have inconsistent morphology or habits and may represent one variety more than another, or can be equal admixtures. LINK: Distribution of Redbud (Cercis canadensis) Varieties in Texas http://opuntiads.com/other/texas-redbud/… The really interesting thing is that one hybrid swarm (D) appears not to mark the boundary between two varieties (at least in Texas). Rather this swarm (mixture of var. mexicana and var. texensis) is like a spur driving north out of Mexico. The distribution is interesting because it splits var. texensis into to disjunct populations within the state of Texas. See the map, magenta counties (labeled "D"). Back to bulbs: hybrid swarms are common in nature. Species are real, and do occur, but they are unpredictable and need not be spread out in a geographically "logical" manner. Hybrid swarms may be clines (and so represnet a gradual change of characteristics over distance), but swarms can also be a confusion, a mix of features. From all of this I infer that field botanists and ecologists, those who laboriously study plants in Nature, county by county and field by field, are true heroes in helping us understand plant species and their endless varieties and distributions. I think geophytes can present especially challenging objects of study because they may only be above ground a few weeks each year, or every other year, and they may have ephemeral flowers. A visit to a locality might not reveal the presence of any plants, yet a visit two months later could uncover vast populations (e.g., Herbertia lahue in Texas). Cordially, Joe Conroe TX
