2019 - Robert's botanical adventures in Northern California

[Robert]

Gerd,

I have observed considerable genetic variance in the varieties of Viola purpurea that grow in our area. They are not difficult from seed, so maybe something good will eventual come from this. Viola pinetorum is a real gen too. Current I am aware of only one population in our area. I will be visiting this stand this summer and I hope that I can get the timing right. Viola purpurea ssp. mesophyta is nice too. I know of only one pure stand. The other populations have turned out to be Viola tomentosa x V. purpurea ssp. integrifolia hybrids. They are nice plants too. I believe you are growing some seedlings from one of the hybrid groups. They will be tricky to grow on beyond the first season. Sorry for the taxonomic mix up on these. Even the professional botanist that I brought to see the blooming plants could not identify them. Field work is not always easy and can even be challenging for professionals.

[Gerdk]

Thank you for the hints Robert!
I agree that all species mentioned are not too difficult to germinate. To keep them growing on is the challenge. From your Viola tomentosa seed (or its hybrid) I sadly received only one quite tomentose seedling which is very slowly growing on despite of 'vip treatment'. V. purpurea mesophyta looks fine and I am looking forward to next season.

Gerd

[Robert]

Gerd,

The Viola tomentosa seed is true to type.

I need additional study to have a better idea how to cultivate this species. The environment where they grow is extremely hot and xeric during the summertime. Almost always I find them growing in granodiorite grus or similar soils derived from granodiorite. They always have apical growth points buried underground. 2 to 4 cm is the general depth. This seems significant for successful cultivation. During the summer the below ground apical growth points stay relatively cool and dry. The root system penetrates deeply into the ground where there is some moisture during the summer and autumn. In small containers, excessive heat conductivity presents cultivation issues that need to be addressed, especially here in our Sacramento garden where air temperatures can reach 40 C during the summer. Soil temperatures in small containers can reach 40 C and sometimes much more if the pots are in the sun. The plants can basically solar cook! I find that large containers ameliorate the build up of excessive heat. I have had success transplanting seed pans as a complete block of seedlings into large containers as soon as possible after germination of the seeds. Getting the seedlings established in the large containers quickly seems to help a great deal. I also suspect that the roots are retractable and that the apical growth points are drawn down to an appropriate depth when the seedlings are transplanted earlier rather than later.

The seed of Viola purpurea ssp. mesophyta should have read aff. I apologize for my mistake. I am quite certain that this batch of seed represents Viola tomentosa x V. purpurea ssp. integrifolia hybrids. They will most likely be much easier to grow. In the wild they grow where the soil is very different from that of Viola tomentosa. The soil is of a much finer texture, much deeper, less rocky, and has a grater percentage of organic material. In addition, they share their growing space with a variety of other plant species. Viola tomentosa is generally found in a much more stark landscape with other plant species spaced much farther apart.

Anyway, I am slowly unraveling some of the mysteries of these species and hybrids and gaining a better understanding of our native Viola species. There is still a great deal for me to learn and understand, but steady progress is being made.

[Robert]

This is my busy season. 

I am currently working on a summary of my 30 May outing which I will start posting after a few days. 

[Gerdk]

Thank you once again Robert for the detailed explanations concerning the viola species mentioned above.
Am I right when I suggest that the soil for both has a lower ph Level?

Gerd

[Robert]

Gerd,

And thank you for your input and expertise concerning these species. Everybody can benefit. 

I now have funding for my projects in the Sierra Nevada Mountains and will purchasing more data recording instruments. I have one site where I am recording heat fluxes in the soil at various depths, as well as outgoing longwave radiation. The data has application in horticulture and is extremely fascinating and revealing. Even the surface energy budget is intertwined and interacts with the vegetation of any given site. The short of all of this is that I will have much more detailed site specific data for many more sites in the near future.

On Peavine Ridge both Viola sheltonii and Viola purpurea ssp. integrifolia grow in a very fine textured andesite based soil that is fairly deep. The soil Ph is approx. 6.0. I have the exact figures, but they are not right in front of me presently.

Thank you again for your input and perspective.     

[Robert]

LYONS CREEK
RIVERTON & PEAVINE RIDGE
El Dorado County, California

Part I

Thursday, 30 May 2019

Weather for selected location

Lyons Creek, 6,725 feet, 2,050 meters
Weather: Thunderstorms
Temperature, High: 55 F, 12.8 C
                       Low: 31 F, -0.6 C
Relative Humidity: 100%
Dew Point: 39 F, 3.9 C
Wind: SE Calm
Precipitation: 1.25 inches (31.75 mm)




Early in the morning on 30 May 2019 I set off for the Sierra Nevada Mountains to do some botanical fieldwork and download meteorological field data at several sites. My first stop was the Lyons Creek basin, elevation 6,725 feet, 2,050 meters. Earlier in the month of May, there were a number of late season snow events in the high elevations of the Sierra Nevada, so there was basically no change in accumulated snowpack in this area compared to my last visit in mid-May.



The access road into the Lyons Creek – Wrights Lake area was still impassible due to the deep snowpack, still measuring 1.2 meters on average. Fortunately, the early morning snow cover was firm and easy to hike over.



The water in Lyons Creek was still very cold and running high. At 34.0 F, 1.1 C, the water temperature was basically unchanged from my last visit on 15 May. The water levels were much lower during this visit, however this time of year there can be large diurnal fluctuations in the water levels and flow rates, so accurate comparisons based on simple short-term observations are difficult



Although the snowpack was basically unchanged over the two-week period between my visits to this area, solar radiation had clearly eroded the snow in the sunniest sites. In some locations the ground was bare of snow, while only a few meters distance away drifts of snow could still be 2 meters or more in depth.



Through the break in the trees at the Lyons Creek bridge, I could see snow capped Pyramid Peak in the distance.

[Robert]

Although there was little open ground, I decided to hike up the Lyons Creek trail to see what I might find. This was my view as I set off up the trail. As one can see, my prospects of finding much in the way of perennial plant life emerging from the ground looked inauspicious.



My efforts were not fruitless. I did find many sites where the snow cover had melted away and the plants were newly emerging from the ground.



There was plenty of standing and running water where the snow had melted away. Having site-specific meteorological data is invaluable in the evaluation of situations as pictured. Although recent low temperatures had been only slightly below freezing, previous to this time there had been some extremely cold temperatures. Such information helps me to evaluate cold temperature tolerance as plants emerge from the ground after snowmelt.



As an example, I had found a few open flowers on a few specimens of Ranunculus alismifolius var. hartwegii on my previous visit two weeks prior. Although the newly emerged vegetative growth had been unharmed by the cold temperatures, there was evidence that the extreme cold temperatures damaged some of the flowers earlier in the week. How different mountain species cope with cold temperatures during different times in their growth cycles varies.



I actually encountered a few fairly large areas of open ground. The situation pictured is very typical of many snowmelt/snowfield species. Frequently there is a delayed reaction by the plants when the snow first melts. After snowmelt, many species delay new growth and emergence from the ground for up to two weeks to avoid extremes in cold temperatures and tissue damage. Here it is easy to determine where the snow first melted away.

[Robert]

LYONS CREEK
RIVERTON & PEAVINE RIDGE
El Dorado County, California

Part II

In this photograph one can see residual snow in the lower right hand corner of the photograph. The sad looking plant is Eriogonum marifolium. This is an effective strategy that some plants use to avoid cold weather damage to their tissues.



This is an example of Eriogonum marifolium after the plant has restored and resumed full photosynthetic capabilities after snow melt. This process can take anywhere between 5 and 14 days depending on the weather and the species.



In this photograph Horkelia fusca var. parviflora has resumed active growth. During the previous season there was very little snow cover during much of the winter in the Sierra Nevada Mountains. I visited this site briefly during this time period to observe the response of the plants to cold winter temperatures without snow cover. Although this species appeared desiccated and lifeless there were very few losses among the populations at this site. When a variable/variables changes slightly the results can be very different.



Once again there was a threat of thunderstorms this day. For various reasons I was keeping an eye on the convective cloudiness and storm development. Earlier in the morning, before the sun rose, I had observed residual turrets of convective cloudiness from the previous day as I drove toward the site. As the morning progressed, this remnant of the atmospheric boundary layer from the pervious day broke down and the clouds disappeared. Later in the morning as the sun started to warm the surface of the ground, convective cloudiness began to appear again. What was extremely fascinating was how the pattern of convective cloudiness was partly governed by the albedo of the land surface in various areas.



I had finished my work in the Lyons Creek area and moved down the mountain to a low elevation site in the canyon of the South Fork of the American River. Here spring was in full swing and there were many species of plants in bloom.

Hosackia crassifolia var. crassifolia is a very common species in this region. It was one of many plant species that had begun their blooming cycle for the season at this site.

[Robert]

Like Hosackia crassicaulis, Lathyrus sulphereus is another member of the Fabaceae family. They were seen scrabbling over the ground and climbing through low shrubs at this site.



Triteleia ixioides, represented in the form of one subspecies or another, can be found over a very large altitude range in California. This species can be found from near sea level into the upper montane life zones of the Sierra Nevada Mountains. At this site this species is represented by subspecies scabra. This is one of three subspecies that I find in El Dorado County, California.



The Fabeacea Family was well represented at this site. The low spreading Acmispon nevadensis var. nevadensis had opened its bright yellow, yellow-orange/red flowers in sunny site along the sloping terrain.



I found a few colonies of the California native annual, Diplicus (Mimulus) kelloggii at this site. On a previous visit to this area this spring I had observed large colonies of this species on the canyon slopes. This diminutive species is a very showy species when in bloom.



The tiny annual Leptosiphon ciliatus were found scattered throughout sunny portions of the steep south facing canyon slopes. Their tiny pink flowers are very cheery.

[Robert]

Rossettes of Phacelia heterophylla var. virgata were sending up their flowering stems. In general, Phacelia species attract a many of insect pollinators to their open flowers. Because of this quality, they are outstanding species for attracting native insect life to the garden.



Iris hartwegii ssp. hartwegii is well represented in this area. It is quite common to find large clumps of this species in the lower montane life zones. This species can be found at site up to 5,500 feet (1,676 meters) in elevation. The high elevation colonies generally are found in thermal belts at the high end of their altitude range.



The insect life has become very active with the warm spring weather. Insects are very fascinating. This Bluet, Enallagma sp., was perched on this leaf as it hunted for food.



There were thousands of Painted Ladies, Vanessa cardui, active on the steep slopes. Rose Clover, Trifolium hirtum, is a common invasive species in our part of California and the species was blooming everywhere. This was to the liking of the Painted Ladies, as many were feeding on the open flowers.



The day was progressing and it was time to move onward to the crest of Peavine Ridge. The thunderstorm activity was building and moving westward toward the area I was working.

Studying circulation flows in mountain thunderstorms is extremely fascinating. Circulation flows within all thunderstorms follow general patterns. However, mountains terrain can create subtle alterations in these circulation patterns, which in turn can alter the development and life of mountain thunderstorms. I am not a storm chaser, but I do observe the storms from a save distance. Analyzing satellite and radar data is about as safe as one can get, but visual observations and post storm observations can provide important details about the storms.

[Robert]

LYONS CREEK
RIVERTON & PEAVINE RIDGE
El Dorado County, California

Part III

A thunderstorm was drifting toward the area. I did not want to get caught in the rain or exposed to the cloud to ground lightning. I did my best to quickly survey the site and take in what I could.

It was the peak of the blooming season for Viola purpurea ssp. integrifolia. In some locations there were hundreds of plants in bloom.



With Viola purpurea ssp. integrifolia, I generally take the time to examine a sampling of the population very closely. Unfortunately I felt hurried by the impending thunderstorm and the fact that there was much I wanted to see in this area.



Among the andesite rocks Allium obtusum var. conspicuum was in bloom. I find both variety conspicuum and variety obtusum on Peavine Ridge and the adjacent Telephone Ridge. I have never found them in mixed stands in this area, nor have I found populations with a gradation in flower color. It seems that there would be some mixing between the two varieties, but I have never found any evidence that this is occurring.



Despite frequent thunderstorm activity and moist soil, Lewisia triphylla was showing signs of entering dormancy. This tiny species is found in vernally wet sites that become parched dry by summer. This species is bulbous and flowers quickly before entering dormancy as the soil becomes dry.



Triteleia ixioides ssp. unifolia grows abundantly in the “barren” andesite rock fields on Peavine Ridge. Triteleia ixioides ssp. scabra can also be found on Peavine Ridge, however it has a distinct preference for open wooded sites on soils derived from Shoo Fly Formation metamorphic rock.

[Robert]

On Peavine Ridge, Arctostaphylos viscida ssp. viscida is generally the last Manzanita species to bloom in the area. There is a lot of overlap in the blooming phenology between the three species of Arctostaphylos that grow on Peavine and Telephone Ridges. Depending on weather conditions Arctostaphylos mewukka ssp. mewukka can start blooming as early as January with Arctostaphylos viscida often finishing its blooming cycle in mid-June. Manzanita flowers provide an important nectar source for many insects and hummingbirds very early in the season.



I found the native annual Erythranthe (Mimulus) bicolor blooming on 8 May of this year on Telephone Ridge. At that time the weather was hot and dry, with the ground quickly drying. At this time, it appeared the blooming season for this species would be sparse and short lived. The cool and wet weather that arrived later in May as well as the extended thunderstorm activity in June revived the fading season for this species. As of this writing, 15 June, large blooming colonies of this species can be seen on both Peavine Ridge and Telephone Ridge. It is amazing to see how resilient and flexible many species are in coping with changing environmental conditions.



In an open wooded site I found Fritillaria micrantha in bloom. This is not an easy species for me to photograph. This photograph is about as good as it gets for me. The flowers of this species have a considerable color range. Maybe in the future I will be better able to document this variety in flower with photographs.



Castilleja applegatei ssp. pinetorum was in full bloom in scattered sites on the Ridge. This species thrives in full sun in the andesite rock fields.



Another lovely annual species is Clarkia arcuata. This species was just coming into bloom when I visited Peavine Ridge on this outing. Since this time I have returned to the area where thousands of Clarkia arcuata flowers can now be seen. Additional Clarkia species grow on Peavine and Telephone Ridges. They will start blooming a bit later in the season.

[Robert]

Navarretia prolifera ssp. lutea is another annual species found in the Peavine – Telephone Ridge areas. This tiny species is rare in nature. Fortunately the populations in this area seem well protected.

After racing around, the lightning strikes came too close for my comfort. It was time to leave the area and return home. As usual, I had a delightful and very productive outing.

Until the next time…

[Robert]

LYONS CREEK BASIN
El Dorado County, California

Wednesday, 12 June 2019

Part I

Weather for selected location

Lyons Creek Basin, 6,725 feet, 2,050 meters
Weather: High Clouds
Temperature, High: 76 F, 24.4 C
                       Low: 40 F, 4.4 C
Relative Humidity: 40%
Dew Point: 43 F, 6.1 C
Wind: NW 2 G 4
Precipitation: 0.00 inches (0.0 mm)





On Wednesday, 12 June, I returned to the Lyons Creek Basin to monitor snowmelt conditions and record data on the emerging flora. I was hoping that after two weeks of, at times, hot weather that the access road into the Basin would be free of snow. Although much of the road was free of snow there were still some deep drifts of snow that prevented access to the basin by auto. The short hike into the Basin is pleasant and also revealing if one is observant, so the hike did not disappoint me.

It was a pleasant morning and there would be no threat of thunderstorm activity on this day. I could take time to make detailed observations and spend most of the day in the region without having to be concerned about stormy weather.

As I am on the topic of weather, I am currently monitoring incoming short wave radiation (e.g. direct beam solar radiation) throughout the high elevations of this region. Of course, cloud cover influences the amount of solar radiation that is received at the earth’s surface. It is well established that the Sierra Nevada Mountains receive a great deal of solar radiation during the summer months. Analyzing the actual numbers is extremely interesting. There is a relationship between incoming solar radiation, cloud cover, summertime thunderstorm activity and the behavior of plant communities. It is nice to be in a position where I can connect these variables with horticultural applications in mind.

Before proceeding for the day, I recorded data on water temperatures and flow rates in Lyons Creek. With hot summertime temperatures Lyons Creek was flowing high, even for the morning hours. The water temperature is now beginning to rise, now 39.0 F (3.9 C), as the bulk of the snow at this elevation has melted away and air temperatures are rising.



The landscape is not completely free of snow and ice, but there are large areas free of snow. On somewhat level terrain, almost everything is flooded. The scenes and conditions are very similar to those I encountered at the Montane Basin many weeks ago. Where the snow is gone, plants are emerging from the ground everywhere. Nighttime temperatures have moderated a great deal, and freezing nighttime temperatures have almost ended.



This would be my fourth venture up the Lyons Creek Trail this season, and the first where some sections of the trail would be snow free. Much of the trail and surrounding landscape would be flooded with standing or flowing water, but these are typical conditions for this site in the spring snowmelt season.



Ranunculus alismifolius var. hartwegii is among the earliest to emerge after snowmelt and come into bloom. In some locations there were already large sheets of this species in full bloom.



Caltha leptosepala is another species that is very early to emerge after snowmelt. This species becomes active even before the snow has completely melted from a site. It is not unusual to see the foliage and open flowers appearing through a thin layer of snow. The species is also moisture loving and is most likely to be seen in, or near, shallow flowing water.