Tuesday, June 29, 2010

Ring Mountain Open Space Preserve

Ring Mountain Open Space preserve is one of the best things about living in San Francisco if you're a plant nerd. A short 20-30 minute drive across the Golden Gate Bridge and into southern Marin County and you're standing on a small hill surrounded by stunningly beautiful native flowers while enjoying postcard perfect views of San Francisco and Mt. Tamalpais.

San Francisco as seen from Ring Mountain in April
Once upon a time (ohh, say, the 1950s) the urban planners in the Bay Area were busily deciding how to manage the relentless growth the post-war economy brought to the region. One of those unrealized plans had a lovely 6 lane freeway perched along the ridgetop of the Tiburon Peninsula connecting to a new bridge to San Francisco via Angel Island and Alcatraz Island. Ring Mountain, located at the start of the peninsula, was slated to be topped/leveled and a regional shopping mall placed there, with convenient access to San Francisco provided by this wonderful new bridge and freeway.

Mt. Tamalpais as seen from Ring Mountain
Thankfully we had our freeway revolt and this plan never happened. Ring Mountain remained undeveloped and in the early 1970s a spectacular flower was discovered, a species of Calochortus, that would finally seal the deal for Ring Mountain to forever remain open space.

You may be noticing a theme in my blog posts. Serpentine. Ring Mountain is full of it, and in fact, the rarity of many of the flowers found on the mountain is due to the serpentine outcrops found there. Calochortus tiburonensis, Allium lacunosum var. lacunosum,  Monardella purpurea, and more are serpentine species. This lucky happenstance of plate tectonics gives Northern California its full and fascinating flower diversity. The mountain seems to have something interesting in flower from mid-March through June and into July. Let's check out some of the more interesting species and when they bloom:

Calochortus umbellatus, mid-March
Lasthenia californica, mid-March
Dodecatheon hendersonii, mid-March
Tauschia kelloggii, mid-march
Toxicscordion species, mid-March
Leptosiphon androsaceus, mid-April
Sidalcea malviflora var. laciniata, mid-April
Layia platyglossa, mid-April
Achillea millefolium, mid-April
Ranunculus californicus, mid-April
Sisyrinchium bellum, mid-April
Calochortus umbellatus, mid-April
Thermopsis californica, mid-April
Calochortus tiburonensis, late May
Allium lacunosum var. lacunosum, late May
Eriophyllum confertiflorum var. confertiflorum, late May
Hesperolinon congestum, late May
Castilleja rubicundula ssp. lithospermoides, late May
Delphinium hesperium ssp. hesperium, late May
Silene californica, late May
Triteleia peduncularis, late May
Monardella purpurea, mid-June
Clarkia rubicunda, mid-June
Dudleya cymosa, mid-June
Eriogonum luteolum var. caninum, mid-June
Hemizonia congesta ssp. lutescens, mid-June

Thursday, June 24, 2010

Brassicaceae in California

Northern California contains a bounty of species, both native and introduced, of plants in the mustard family, Brassicaceae.

Check out the wide variety of species I've photographed.
Click each photo to learn more:
Erysimum capitatum

Streptanthus hispidus
Arabis blepharophylla
Erysimum species
Cardamine californica
Streptanthus niger


Erysimum capitatum
Arabis breweri
Draba lemmonii
Non-native Mustard fields at Pt. Reyes National Seashore
Cakile maritima, non-native
Streptanthus hispidus

Calochortus superbus

This is my first year seeing a large number of this species in bloom. I first encountered it up in Glenn County as a few individuals growing among a large patch of C. luteus  and then more recently was told about a very large population growing in the exurbs near Placerville, California.

The species grows in clay soils and is tolerant of serpentine. The flowers are usually creamy with a noticeable blotch surrounded by yellow. The most easily seen diagnostic feature is the inverted-v shape of the gland. It has a very wide range, from the North Coast Ranges to the Sierras and south to Mt. Palomar in southern California.

Today's photos are from the population in El Dorado County, near Placerville.









Wednesday, June 23, 2010

Lake Leatherwood

Lake Leatherwood Dam, Eureka Springs
Lake Leatherwood is a spring fed montane lake in the Ozarks of northwestern Arkansas. It's right outside the 19th century 'healing waters' health resort of Eureka Springs. The entire area is still relatively wild, with several national forests and state parks within easy driving distance.

The lake and dam were part of the Works Progress Association stimulus efforts to get people working during and immediately after the Great Depression of the early 20th century. The lake is surrounded by a beautiful second growth forest with pockets of cedar glades and still retains a fairly diverse flora.
Mixed Broadleaf Forest

This region of Arkansas is the western edge of the Southeastern coniferous and broadleaf forest ecoregion, an ecoregion with almost 200 tree species, over 35 of which are endemic. This particular ecoregion has more than 3500 species of herbs and shrubs, the highest species count of any bioregion in North America.
Glandularia canadensis

Brian and I took a 3-4 hour walk around the perimeter trail surrounding the lake. I was optimistic we would see some nice flowers and wasn't disappointed. We parked at an open clearing with picnic tables and a view of the lake water through some trees and then headed towards the start of the trail, which resembled what we call in California a fire road. We saw lots of Glandularia canadensis, a lovely spring flower in the Verbenaceae, growing in a large clump at the start of the trail. A good sign!

Once on the trail the dominant floral feature was incredible diversity of trees and shrubs. The trees had just finished leafing out and many were still a pale, bright green, in contrast to the darker rich green they attain after full leaf out. Looking up over our heads we found mid-sized shrubs and small trees glowing green in the dappled morning light, with species such as Celtis laevigata, Quercus muehlenbergii, and Cornus florida providing rich textures.

Lithospermum canescens
Wandering up a short spur trail higher along the ridge we found our first cedar glades where ferns, Lithospermum canescens and Hypoxis hirsuta were abundant. The Hypoxis in particular seemed to be an indicator species for the presence of a glade. Additional flowering herbs along this side trail included Enemion biternatum, Phlox divaricata, Oxalis violacea, and Cynoglossum virginianum. Two of the more impressive flowering shrubs were Viburnum rufidulum and Vaccinium stamineum.
Camassia scilloides

I was excited to encounter my first geophyte, Camassia scilloides. This spring bulb has pale blue flowers with bright yellow stamens. As we continued walking we saw Ranunculus recurvatus, Senecio aureus, Aesculus glabra, and our second geophyte, Trillium viridescens.

We'd reached the approximately halfway point by this time. The trail so far was too far inland from the lake shore for us to really see the lake but now we had to cross the dam to reach the other side. Good things come to those who wait! We were literally speechless at the sight of the dam and then the lake itself as we crossed. The lake is surrounded on both sides by gentle rolling hills, carpeted in dozens of shades of green with a heavy popcorn cloud cover overhead. The area has had a wet winter and spring so the spillway to the dam was in full operation, adding another beautiful component to the walk.
Lake Leatherwood Dam
Delphinium tricorne
Once we reached the opposite shore we quickly found ourselves walking through an old limestone quarry. Our guide book told us this was the quarry where the WPA quarried the limestone facing blocks for the dam! The resulting return to nature more closely resembled a cedar glade than a forest. Juniperus virginiana were growing in stunted forms from the cracks in the granite and there were large patches of Minuartia patula here and there. But what we enjoyed most about the quarry were the thousands and thousands of tadpoles! I'd never seen so many tadpoles in one place. That really spoke to the high quality of the local ecosystem.
Tadpoles!

As we continued hiking we crossed several more tranquil cedar glades. We were also much closer to the shore and enjoyed the varying views as the lake came into view from time to time.

Towards the three quarters mark we hit Leatherwood Creek, which feeds into the lake, and the plant communities changed dramatically. We encountered large populations of Podophyllum peltatum, Pedicularis canadensis, Polemonium reptans, Asarum canadense, Tradescantia species, Trillium viridescens, and my favorite flower from the whole day, Delphinium tricorne.

More flowers and scenery from the hike:
Brian walking in the forest

Podophyllum peltatum
Lake Leatherwood Dam spillway
Hypoxis hirsuta
Viburnum rufidulum
Asarum canadense