The period December through February is the time of year that has the fewest plant species in bloom. However, that is an advantage for people who want to begin to learn the plants of the Santa Rosa Plateau since it is then much easier to match an observed flower to the list of possible identifications given on this page.
The actual list of species in bloom in winter always depends on the actual weather we've been having and on the weather yet to occur. For example, if there is no rain, and/or if December, January and February are cold months, there will be virtually no flowers in January and February. Some years there are only five species in bloom during most of December through February, such as 2001 and 2003.
On the other hand, if we get early rains in October to mid-December, and then it stops raining and turns hot, a lot of species will begin to bloom in January. There have been as many as 20 species blooming in January, and 40 in February, in past years, such as 2002.
See plots of the number of species in bloom in recent years. That page also discusses some of the reasons behind the variability in bloom times.
Below I give two separate lists. The first contains a short list of 14 species that are often observed to be in bloom in January to February even in the worst bloom years for those months.
The second list gives a fairly complete list of 45 species that sometimes have been observed to be in bloom in January to February. This list was made from bloom periods listed in Munz 1974 for all of southern California, and hence may contain some species that never actually bloom at the Santa Rosa Plateau during those months. Someday I'll go over the records from myself, Kay Madore, Gordon House, and vouchers to get bloom times more specific to the Santa Rosa Plateau. Some species have already been added to the list here from my digitized records.
Both lists only contain species that have flowers likely to be noticed by beginners. They therefore contain no species such as grasses, or species with tiny flowers that do not produce noticeable displays.
One way beginners can use these lists to learn the plants at the Santa Rosa Plateau is to use your favorite reference (book or website such as 2000 Bloom Identification Guide For The Santa Rosa Plateau) and look up the 14 species in the first list. Then go into the field, and see if you can find any of them. Alternatively, you can search my list of plant trail guides for the Santa Rosa Plateau to find exactly where these species occur. (Search for "Santa Rosa Plateau", "plant guide", with both of those phrases in separate sets of quotes, and the common or scientific name of the plant species in separate quotes, to get just the list of trails here.)
Alternatively, you can photograph blooms you see in the field at the Santa Rosa Plateau between December 1 and the end of February, and then try to match them up to the species names below. Start with the species in the first list. If you don't find a match, then go through the additional species in the second list. If you still can't find a match, email me your pictures, and if it is a species not in the lists below, I'll add it.
Notes for both tables
Non-native species are indicated by the asterisk before their common name.
The species are arranged in traditional family order, since that keeps closely-related species together.
The tables give the number of plant trail guides on which each species occurs. The maximum number is 16. Here are some tips on how to use this number:
- If you have seen a given species on three trails, you don't need to look up species that occur on only one trail.
- If you are trying to learn the species by looking them up first, and then heading into the field, concentrate on species found on a large number of trails first.
The complete range of months in which each species has sometimes been observed in bloom is given, with 1=January, 2=February, ..., 12=December. For species which can bloom before and after January 1, in an interval centered around January, their first bloom month is listed as, for example, December, with the last bloom month being, for example, March.
Most plant species are in peak bloom for a period of about three weeks, so most will not be in bloom in any given year in the complete range given. For example, chocolate lilies are listed as having been observed blooming in February through June in past years. However, in 2001 their peak bloom was March 16 to April 8, whereas in 1996 and 1997 there were some blooms in February.
Also, if a species is listed as possibly blooming from February through June, it is much less likely that you will observe that species in bloom in February than another species listed as blooming from January through March.
Be aware that most of the species get on this list because they sometimes or often bloom at the end of February. In December, don't expect to see more than 5-10 species in bloom.
This short list contains 14 species that are often observed to be in bloom sometime during December to February even in the worst bloom years for those months.
Plant Species Typically In Bloom In December Through February
Family Scientific Name (*)Common Name # Trails Begin Bloom End bloom Apiaceae Lomatium utriculatum common lomatium 3 2 4 Asteraceae Blennosperma nanum var. nanum yellow carpet 1 2 4 Asteraceae Gnaphalium bicolor bicolored everlasting 5 1 5 Brassicaceae Hirschfeldia incana *shortpod mustard 16 1 12 Cucurbitaceae Marah macrocarpus var. macrocarpus wild-cucumber 12 1 4 Ericaceae Arctostaphylos glandulosa ssp. zacaensis Eastwood manzanita 3 1 4 Fabaceae Lupinus excubitus var. hallii bush lupine 8 2 6 Geraniaceae Erodium brachycarpum *short-fruited filaree 14 2 8 Geraniaceae Erodium cicutarium *redstem filaree 14 2 5 Grossulariaceae Ribes indecorum white-flowering currant 14 11 3 Papaveraceae Eschscholzia californica California poppy 11 2 9 Polemoniaceae Linanthus dianthiflorus ground pink 6 2 4 Primulaceae Dodecatheon clevelandii ssp. clevelandii shooting star 7 1 4 Ranunculaceae Ranunculus occidentalis western buttercup 5 2 5
This longer list contains species that have sometimes been observed to be in bloom sometime during December to February. It includes the species in the first list above, so that the following list is complete.
Plant Species Sometimes In Bloom In December Through February
Family Scientific Name (*)Common Name # Trails Begin Bloom End bloom Anacardiaceae Malosma laurina laurel sumac 11 2 5 Apiaceae Lomatium lucidum shiny lomatium 2 1 4 Apiaceae Lomatium utriculatum common lomatium 3 2 4 Asteraceae Baccharis salicifolia mule fat 10 1 12 Asteraceae Blennosperma nanum var. nanum yellow carpet 1 2 4 Asteraceae Eriophyllum confertiflorum var. confertiflorum golden yarrow 12 1 7 Asteraceae Gnaphalium bicolor bicolored everlasting 5 1 5 Asteraceae Gnaphalium californicum California everlasting 15 1 7 Asteraceae Heterotheca grandiflora telegraph weed 14 1 12 Asteraceae Lasthenia californica goldfields 6 2 6 Asteraceae Senecio vulgaris *common groundsel 4 1 12 Asteraceae Sonchus asper ssp. asper *prickly sow thistle 15 1 12 Asteraceae Sonchus oleraceus *sow thistle 16 1 12 Brassicaceae Capsella bursa-pastoris *shepherd's purse 6 1 12 Brassicaceae Cardamine californica var. californica milk maids 5 2 5 Brassicaceae Hirschfeldia incana *shortpod mustard 16 1 12 Caryophyllaceae Silene gallica *windmill pink 15 2 6 Cucurbitaceae Marah macrocarpus var. macrocarpus wild-cucumber 12 1 4 Ericaceae Arctostaphylos glandulosa ssp. zacaensis Eastwood manzanita 3 1 4 Ericaceae Arctostaphylos rainbowensis Rainbow manzanita 1 1 4 Ericaceae Xylococcus bicolor mission manzanita 3 2 2 Fabaceae Astragalus pomonensis Pomona locoweed 11 2 6 Fabaceae Lupinus excubitus var. hallii bush lupine 8 2 6 Geraniaceae Erodium brachycarpum *short-fruited filaree 14 2 8 Geraniaceae Erodium cicutarium *redstem filaree 14 2 5 Geraniaceae Erodium moschatum *white-stemmed filaree 7 2 5 Grossulariaceae Ribes indecorum white-flowering currant 14 11 3 Hydrophyllaceae Nemophila menziesii var. menziesii baby blue eyes 3 2 6 Malvaceae Sidalcea malviflora ssp. sparsifolia checkerbloom 16 2 7 Nyctaginaceae Mirabilis californica California four o'clock 6 12 6 Paeoniaceae Paeonia californica California peony 10 1 3 Papaveraceae Eschscholzia californica California poppy 11 2 9 Polemoniaceae Linanthus dianthiflorus ground pink 6 2 4 Portulacaceae Calandrinia ciliata red maids 8 2 5 Portulacaceae Claytonia parviflora ssp. parviflora narrow-leaved miner's lettuce 5 2 5 Portulacaceae Claytonia perfoliata ssp. mexicana southern miner's lettuce 12 2 5 Portulacaceae Claytonia perfoliata ssp. perfoliata miner's lettuce 6 2 5 Primulaceae Dodecatheon clevelandii ssp. clevelandii shooting star 7 1 4 Ranunculaceae Ranunculus occidentalis western buttercup 5 2 5 Rhamnaceae Ceanothus crassifolius hoaryleaf ceanothus 3 1 4 Saxifragaceae Jepsonia parryi coast jepsonia 8 10 1 Saxifragaceae Lithophragma affine woodland star 3 2 6 Violaceae Viola pedunculata johnny jump-up 14 2 4 Liliaceae Dichelostemma capitatum ssp. capitatum blue dicks 16 2 5 Liliaceae Fritillaria biflora var. biflora chocolate lily 4 2 6
Copyright © 2007 by Tom Chester.
Permission is freely granted to reproduce any or all of this page as long as credit is given to me at this source:
Comments and feedback: Tom Chester
Updated 4 December 2007.