Some thoughts abouts plants in Pennsylvania and anywhere else we travel

PA Plantings Blog Home

Including the new home for news and reports of the
Muhlenberg Botanic Club of Lancaster, PA

Pa Plantings Web Web Site Home
including other information about plants

All photographs copyright by Mike Slater unless otherwise noted.

Saturday, August 18, 2007

A Blue Lettuce Day














































A Blue Lettuce Day Aug 17, 2007

(Lactuca floridana that is!) plus two other new plants!

(Pictured above, from top to bottom, Pellaea glabella, Asplenium trichomanes, Ludwigia hexapetala*, Lactuca floridana a 7 foot tall plant and a close-up of the flower)

Yesterday Tim Draude and Joan King came up from Lancaster to the Reading area in Berks County to look at ferns and wildflowers with me. I wanted to show them the nice, easily accessible, cliff/wall ferns at Gring's Mill County Park and Gibraltar Aqueduct, including Pellaea glabella ssp. glabella, Pellaea atropurpurea, Asplenium platyneuron, Asplenium trichomanes, Woodsia obtusa and get confirmation of the id. of Cystopteris tennuis. All the ferns were in fine shape and easy to study.

In addition I was hoping that with their sharp eyes and knowledge of native plants they would spot interesting plants with which I was unfamiliar. Not only did we find three very nice species of native wildflowers that I didn't know, They were three that neither Tim nor Joan had ever seen! They had been looking for two of the species for a while though.

At Gring's Mill in a soft muddy area next just upstream from the mill in a wet area (no standing water now after the relatively dry weather we have had but we had to be a little care of the soft mud) next to a large patch of Iris pseudacorus and mixed in with a Sagittaria species was a large patch (over 50' in diameter) of a bright yellow five-petaled flower on soft-hairy, two foot stems that none of us were familiar with. After looking in a field guide we decided it was probably Ludwigia peploides but when we keyed it out in “Gleason and Cronquist” we determined later that with upright, fuzzy stems it was Ludwigia uruguayensis (Water primrose) now subsumed into Ludwigia hexapetala.

It will be interesting to see if that is the name it stays under when the 2nd edition of “the Plants of Pennsylvania” comes out, which I hope will be very soon. This is probably introduced from the southeastern states, but is native to eastern North America as well as south America all the way to Argentina. Both species have records in the “Atlas of the Flora of PA” in the Reading area. This beautiful and impressive plant, Water-primrose, looks like it might be invasive but there aren't many stations for it in the atlas and we only saw it in the one large patch, there we no stragglers in the nearby wet spots.

*I know it only has 5 petals, either the botanist who named it couldn't count, or it has sometimes has six petals or the type specimen was so bad the petals couldn't be counted properly.

The second new plant we found was along a country road in the red Triassic sandstone area south of Birdsboro. Tim said: “That looked like a blue lettuce.” as were driving and I turned the car around and we went back to lookI was indeed a wonderful tall blue flowered lettuce, Lactuca floridana, which none of us had ever seen. The plants (at least a dozen of them in bloom) were about 7 or 8 feet tall with clear blue flowers and with each black seed attachetd to bright white pappus (the "parachute"). The flowers look like small chicory flowers and they were almost as dark blue The inflorescene is rather large and the flowers are spread out so it is not a really conspicuous plant, but it is the nicest wild lettuce species I have seen. There were many first year plants around of this biennial species so the population seems to be reproducing well, but it is near a driveway where it would only take two minutes with a weed-eater to eliminate the population.

Then we went to the Birdsboro Reservoir and had a pleasant walk though the wood and up to the lake discussing/puzzling over several Desmodium species (tick-trefoils) and Helianthus decapetalus/H. tuberosus (Thin-leaved sunflower/Jerusalem artichoke hybrid possibilities. At the lake we spotted a small group of three foot tall, white flowered, Eupatorium species which looked very stiff, with wide round toothed leaves. They appeared to be different from species we were familiar with. It is similar to E. sessilifolium but keyed out to be Eupatorium godfreyanum in “Gleason and Cronquist” which is one of the putative parents of this species of hybrid origin. This is not a showy plant but it is not quite OBIO. (of botanical interest only!)

This is a plant which Tim had been looking for on the islands below Holtwood Dam in the Susquehanna River where it has been reported in the past but it is not shown in the “Atlas of the Flora of PA." Since this plant is not officially present in Pennsylvania (but is found in NJ and MD) We will have to do a little more research but it looks promising!

------Update-8/19/07------Pictures Added 8/21/07
After some m,ore checking and comparison and keying we have concluded that it is Eupatorium pilosum, which has been found in this part of Berks County according to the "Atlas of PA Flora".
This is still a new plant for me!

No comments: