Winter vetch is a vining legume you'll see in patches along trails in lower elevation chaparral in Southern California. It's flowers are an unusal purple, and a closer look reveals various shades of violet, purple and rose.

Its capability to add nitrogen to soil gives it value in crop rotation and no-tillage farming. It is an invasive plant, not native to California.

From today's run in the Simi Hills.

From today's trail run to Castle Peak in the western San Fernando Valley.

Updated April 9, 2011.

Chinese houses (Collinsia heterophylla) along the Secret Trail in Calabasas, California. From a trail run on March 30.

Was originally identified as Davidson's Blue-Eyed Mary (Collinsia bartsiifolia var. davidsonii). Took a closer look at flowers in the same colony this year, including  the internal structure of the flower. The presence of a curved basal spur > 1 mm on the two upper (stamen) filaments;  corolla throat as wide as long; and calyx lobes generally sharp-tipped (per key in Jepson) distinguishes the species as the more common Collinsia heterophylla.

From a run this week on the Secret Trail in Calabasas, California.

Fiesta flower (Pholistoma auritum) near Big Cone Camp in Santa Paula Canyon.

This time of year if you're running in Southern California's canyons and notice a subtle, pleasantly pungent, and slightly sweet fragrance wafting about the area, look around, poison oak is probably near.

The small, greenish, five-petaled blossoms generally hide under the "leaves of three" and are easy to miss.

From today's run in the Simi Hills.

Related post: Poison Oak

From today's run in the Malibu Hills.

Winter into Spring the purple flowers of wishbone bush (Mirabilis californica) are found along sun-warmed sections of low elevation trails in much of Southern California.

The plant's common name refers to the stems of the plant, which are repeatedly forked.

From today's run in the Simi Hills.

California peony is fairly common in the Santa Monica Mountains and other lower elevation, open space areas of Southern California. It can be found in a variety of habitats, including Coastal Sage Scrub and Chaparral.

It is a perennial, and has adapted to our demanding climate by dieing back when conditions become hot and dry.   Its leaf growth tends to parallel that of annual grasses, and as these grasses become long, lush and green following early Winter rains, you'll usually find flowering peonies somewhere in the area.

From Saturday's trail run in Malibu Creek State Park.

In the lower elevations of Southern California, miner's lettuce (Claytonia perfoliata) usually sprouts in mid Winter. It is typically found in shady areas of the chaparral understory. It grows in nearly every county of California, and probably occurs in all but the most arid parts of the western U.S.

Miner's Lettuce was reportedly eaten by Gold Rush miners to help prevent scurvy.

From today's run on the Garapito Trail, in the Santa Monica Mountains, near Los Angeles.

If there has been adequate rainfall, shooting stars (prob. Dodecatheon clevelandii ssp. patulum) can germinate and bloom in early January at some lower elevation areas of Southern California.

From a run earlier this week in the Simi Hills.

Related post: Shooting Stars

Following the little bit of wet weather we had at the end of the year, Southern California has been enjoying idyllic weather with highs in the 70's and 80's. Southland cities recorded the highest temperature in the continental U.S. several days this week. Tuesday San Diego recorded a high of 84 degrees, tying Kalaeloa, Hawaii for the warmest temperature in the nation.

The weather's been great for trail running -- and for the chaparral plants. Alternating periods of wet weather and warm weather have encouraged growth and flowering, and I've been seeing a number of rainy season wildflowers. In addition to the milkmaids in the photograph above, some of the early bloomers include nightshade, peony, shooting star, woolly blue curls, prickly phlox, chaparral mallow, rattlesnake weed, and several others.

Rainfall totals in Southern California this rain season to date have generally ranged from an inch or so above normal to an inch or so below (WRCC). As of yesterday, Downtown Los Angeles (USC) precipitation was 0.56 inch above the norm for the water year to date. Although January has been dry so far, it looks like we may see a shift to more seasonable -- and wetter -- weather around midweek next week.

The precipitation pattern we've seen on the West Coast so far this rain season has a bit of an El Nino flavor to it, and that pattern may become better defined in the coming weeks. Today's 6-10 day and 8-14 day precipitation outlooks from the Climate Prediction Center indicate above average rainfall for Southern California. We'll see!