2016-04-22 Milkweed Road Survey; Loop to Brownwood and back

Chalk Mountain, US67, Stephenville, US67, Comanche, US67, Brownwood, FM 573, Goldthwaite, CR2005, FM 218, TX36, Hamilton, US281, Hico

http://www.inaturalist.org/observations?nelat=32.57412928200187&nelng=-96.23611450195312&on=2016-04-22&place_id=any&project_id=texas-milkweeds-and-monarchs&swlat=31.292165125523084&swlng=-99.50729370117188&user_id=gregglee&verifiable=any

Stopped about every ten miles, unless previously surveyed or, no Milkweed (genus Asclepias) visible while driving. We did not stop to do foot search if none visible while driving.

We found Milkweed , mostly A. asperula, on the whole route. Some A. viridis and in one location A. viridiflora. A. asperula were often almost continuous along road. Ratio of A. asperula individual plants to viridis plus viridiflora was 1000:1 or more. Road side grass was frequently high, but even there milkweed was mixed in. Milkweed very obvious on slopes either away from road or on sides of road-cuts. Sometimes visible far beyond the fences.

The only break, aside from towns, was on US67 from Stephenville most of the way to Comanche. Businesses extend well west of Stephenville and most that roadside was mowed. Then the highway had been recently rebuilt including a new bypass around Dublin. Shoulders had been widened and paved, and drainage ditches had been re-contoured by grading. Grass sowed by TXDot and some forbs had grown thickly, but no milkweed large enough to see while driving. I speculate that the dirt work was deep enough along the roadsides to remove the established large milkweed plants and their deep tap roots. New milkweed growth might have been there, but small and hidden by grass and forbs growing fast with recent rain.

So complete road rebuilding appears to be bad for milkweed. Saw similar but lesser effect later on US 281 where new passing lanes have been added over the past couple years. On 281 the disturbed width beyond the road varied. In some areas it was fence to fence; in others only a couple steps from the road. Limited disturbance was often where the roadside sloped or in road cuts through hills. Disturbance was generally wider where roadside was relatively flat. This suggests that TXDOT vehicles driving or regrading may sometimes extend wider than strictly necessary for the work. Disturbance was widest where disturbing was easiest. Will look again next year.

The Invasive Eurobee, Apis mellifera occurred continuously on milkweed and other flowers
throughout trip, often outnumbering native pollinators, and frequently pushing them off flowers.

Posted on Μάιος 01, 2016 0613 ΜΜ by gregglee