Terry Yager wrote:
But, what would happen if an endangered native species of crabgrass were found growing in the middle of someone's $10,00.00 imported-sod Kentucky Blue Grass lawn?
Difficult to picture since crabgrass ain't from the US and is certainally in no threat (well the species I'm thinking of at least).
There's only a couple of reasons why a grass species maybe dying out - certainally Human intenvention could be one, it's only found in one place due to the soil, temperature or other weather conditions & many people have mowed it low - by cutting off the the core of that grass and killing it - or in lots of cases the grass may not like been mowed at all!
If I found such a grass in my lawn (which for the purpose of where I live I've been fortunate of finding a small patch of Wallaby grass), I'd be trying to find out more about that grass - when it grows, flowers and seeds. And collect a small portion of the seed and try and propagate it. Once I've propagated some, I would find a suitable spot for that grass to grow and try and get a colony of that going. I've jumped a little bit there because propagating maybe more complicated than simply collecting the seed and potting it up into trays and watering (certainally for the grasses I've got going they have been straightfoward because they have been successful on their own out in the bush - with the aid of fire or smoke). For propagating I got a suitable book which advises on how to propagate plants and what treatments are available which bring good results. I've also got another list which shows when those species seed (around Christmas time usually). Grass will always generally start growing, produce flowers and eventually those flowers turn to seed - in some cases the seed drops when it's ready so there's a little gap when everything looks ready.
If you were talking about someone elses lawn and you saw something endangered in it - the proper thing to do here is to communicate with that property owner and see if you can get some seed from them. Other services we have here are people which collect local seed stock from particular areas - some services may even carry seed stock for a large area - late last year I visited the botanical gardens in the city which had all these gardens setup from different areas of the state and their theme there was plants which are like you described it - endangered. So it may well be that for your area someone has already come up with that idea of trying to protect endangered plants by collecting the seed and produce and keep seed stock in a well stored area for preservation to protect those species.