Russ- Re "...top of the rocks...", you reminded me of a series of large rock outcroppings on the North Rim of Grand Canyon...in searching for additional populations of a Threatened and Endangered Species sentry milkvetch(Astragalus chremnophylax var. chremnophlyax)...we had to scale uhm shed-size boulders to see if populations had survived there.
To date, none have been found on boulder tops, even though the source of the substrate is near the boulders, the weather is quite similar...the plant's ecology isn't fully understood, as it's currently thought that the pollinating vector could be ants (which could scale the boulders a darn site easier than we were able!). -Don From: [email protected] Date: Fri, 3 Apr 2009 14:37:21 -0400 Subject: [ENTS] Re: exceptional poison ivy To: [email protected] Don: About 250' in elevation above the valley bottom there is a 50' cliff and the rock broke off the cliff at sometime in the past. The rock was cracked and the PI might have caused the crack. In that area there are miles of woodland with a 50' cliff between uplands and lowlands. In some places you will encounter large rocks at the base of the hills that can be up to 50 or 60' across and 30 or more feet thick. In those areas, especially where there has been a long time forest cover the non woody plants growing on top of the rocks in locations that are inaccessible to deer or other types of grazing critters can be diverse enough to cause you to pause...especially if you have a weak spot for rare ferns. Russ Feeling the pinch at the grocery store? Make dinner for $10 or less. _________________________________________________________________ Rediscover Hotmail®: Get e-mail storage that grows with you. http://windowslive.com/RediscoverHotmail?ocid=TXT_TAGLM_WL_HM_Rediscover_Storage1_042009 --~--~---------~--~----~------------~-------~--~----~ Eastern Native Tree Society http://www.nativetreesociety.org Send email to [email protected] Visit this group at http://groups.google.com/group/entstrees?hl=en To unsubscribe send email to [email protected] -~----------~----~----~----~------~----~------~--~---
