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Robert's Crystal Range Project - Year 3, 2021
Robert:
Here it is the start of 2021 and the beginning of year 3 of my Crystal Range Project.
This is a view of the canyon of the South Fork of the American River taken from Peavine Ridge on 21 December 2020. There is very little snow! And total precipitation amounts in our region are running about 30% to 35% of average to date. I am sure I will have much more to discuss on this topic in future postings, but for now the extremely dry condition continue and are forecasted to continue for at least the next 7 days.
This is a view looking up into the higher regions of the canyon of the South Fork of the American River. 40 years ago, during most seasons, this site would have been carpeted with snow on 21 December. Slowly the more subtle impacts of climate change on plants/plant communities are being uncovered.
The crest of the Crystal Range can be seen in the distance. Despite the dry conditions, the snow pack in the higher elevations of the range is maintaining its depth and water content. Now that the winter solstice is past, if clear skies prevail, increasing levels of short wave solar radiation will erode the existing snow pack. This is already occurring at the lower elevations where there is some snow.
Anyway, I hope to get back to the Sierra Nevada soon.
Robert:
I was back in the Sierra Nevada Mountains the other day. It was a beautiful warm day with a high temperature of about 70 F (21.1 C). This is certainly nothing that I would expect in mid-January at the elevation of 5,100 feet (1,554 meters). Yesterday’s high temperature at the farm was 70 F (21.1 C). This was a record high temperature for 15 January.
The extremely dry weather pattern continues. It has been 10 days since there has been measurable precipitation. Our current precipitation total currently stands at 35.1% of average to date. There is no indication there will be meaningful precipitation during the next 7 days. The situation in the Sierra Nevada Mountain is about the same. There is basically no snow below 5,000 feet (1,554 meters) and much below average snow totals above this altitude.
Despite the less than ideal temperature and precipitation pattern, the weather pattern could change later this winter and into the spring. There are indications that the entrenched weather pattern may be shifting. We will see what happens. Last season there was no precipitation during the month of February. Two or three storms during the following months increased precipitation amounts appreciatively.
Eriogonum prattenianum is a fairly common species at the site that I visited.
With Eriogonum prattenianum var. prattenianum, there is considerable genetic variability in leaf retention during the winter among the population observed at this site. Some specimens appear dead, yet they will leaf-out vigorously in the spring. Other specimens will retain a few distally located leaves.
This specimen of Penstemon laetus var. laeatus is sharing space with Elymus multisetus.
Drought stress was considerable this past season. Mortality rates were high among some species, in some cases reaching 51.2% of the observed population. The population of Penstemon leatus var. laetus at this site faired much better, however there were still losses as one can see from this photograph.
Robert:
Aspidotis densa is a very common fern found at this site. Cold temperatures have browned the tips of the foliage (it actually has not been very cold this winter).
Many perennial and annual grasses are now in active growth. The perennial species, Poa secunda ssp. secunda is generally the first to commence active growth when the autumn rains begin.
Elymus multisetus is a perennial bunch grass frequently encountered at this site.
Stipa lemmonii var. lemmonii is yet another perennial bunch grass found at this site.
Other graminoid species can be found at this site. Luzula comosa var. laxa is one of the more commonly observed species. During cold weather the tips of the leaves are frequently colored red with high concentrations of anthocyanin.
Robert:
With the relatively warm weather and the lack of snow cover, many annual species have germinated and are in active growth. This seedling stand of Phacelia stebbinsii has found shelter at the base of this rock. High concentrations of anthocyanin can be seen in the adaxial leaf veining. Abaxially the leaves are frequently richly colored with high concentrations of anthocyanin observable over the complete leave surface. This is not unusual with many annual native species during periods of stress, such as cold weather, drought, or other environmental stresses.
Well it is time to close.
Maggi Young:
Wow! Still so dry!
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