2016 - Robert's adventures in the Northern Sierra Nevada - California

[Tim Ingram]

Catching up and needing it this morning! Wonderful series of outings Robert - you cover so much ground and give so much information, a little more of which sinks in everytime I come to look  . The Manzanitas are truly fascinating and I agree with David about learning more of their potential value in our gardens. I also find the Californian ferns of more and more interest - our summer here was very dry and the garden is developing more and more shade as it matures: ferns are very much on the agenda for future plantings. The Cirsium also interests me - does it have red flowers? I have an old book written by Thomas Hay in 1938 which refers to Cirsium occidentale var. coulteri: "...a most striking and decorative subject, growing five feet high, stout and straight, clothed throughout - leaves, stems and flower-heads - in soft, white cottony wool, and producing its soft scarlet flowers from the axils of every leaf". What a picture! Ron Ratko kindly sent me seed of this years ago but I didn't grow on the young rosettes well enough to reach flowering. Thank you for some reality on an absurd day.

[Robert]

Tim,

Cirsium occidentale var. candidissimum is "red", actually a hard to describe reddish-magenta. The flowers and foliage are very ornamental. The few mature plants I saw (the ones that were not dead) the other day had a few very well worn-out flowers - definitely not worth a photograph but enough to identify.

Yes, there is much I wish to address concerning the Genus Arctostaphylos. Of 100 + taxa, I have personally seen only 20% or so. Of those, there are only 10-15 taxa that I am intimately familiar with. Many California species are native to regions much closer to the Pacific Coast - both Southern and Northern California. Many are very localized endemic species. I am of the opinion that there is still much untapped potential within the Genus. From my Sacramento base the coastal bio-regions are now within my reach. I do hope to elaborate on the potential of the Genus in the future. David has certainly touched on a good topic.

This week I hope to visit a population of Arctostaphylos nissenana on Slate Mountain in El Dorado County, California (near the farm).

[Robert]

Many species of California native plants are highly dependent on fire for seed propagation. Various components in smoke are responsible for enhancing the germination rate of fire dependent species. Artificial smoke products can be purchased. I have used them and I have to admit that they are easy-to-use and more or less effective. I prefer to use the real thing - smoke. I have an inexpensive, low tech smoke chamber that I use to treat my seed pans with smoke. It is effective and, at least for me, easy-to-use.



I found this large plastic container in a pile of junk along our neighborhood street on junking day. I was free for the taking.



This is the set up. An old pie tin (free). The plastic hood to go over both the pie tin and the seed pans.



For smoking, I get a small fire going in the pie tin.



The let the fire consume about 85-90% of the kindling.



Then I pile semi-dry leaves on top of the coals and remaining flames. I end up with a smoldering pan of leaves.

[Robert]

At this time I place pre-watered seed pans and the pie tin of smoldering leaves under the plastic hood.



I let the seed pans smoke for a hour or so. I know when they are done when the grit on top of the seed pans in noticeable discolored by the creosote in the smoke. I then water the seed pans lightly and place them out unprotected to receive natural stratification and rain/snow water. Depending on the species, germination will start in 7-10 days or in the early spring - approximately February-March.

I am completely satisfied with this method. 

[fermi de Sousa]

I'll have to give it a go with some of the South African and Australian seeds which have yet to germinate!
Which American species respond to it, Robert?
cheers
fermi

[Tim Ingram]

Robert, I once tried using 'Hickory Liquid Smoke' (half in jest) with seed of the Californian 'dicentras' (Ehrendorferia). A few germinated but I can't say it was a great success. Your method is simple and straightforward and I must try it. The pictures you showed earlier of Manzanitas in pots appeal to the nurseryman and gardener alike!

[Robert]

I'll have to give it a go with some of the South African and Australian seeds which have yet to germinate!
Which American species respond to it, Robert?
cheers
fermi

Fermi,

A considerable number of California species respond well to this treatment. Off the top of my head I can think of Chaenactis artemisiifolia, Salvia carduacea, and most Arctostaphylos species. I get good germination with Chaenactis in 10 days with this treatment. Without treatment I am lucky to get 2-3 seeds to germinate. With Arctostaphylos it is like a miracle. This seed needs cold stratification too, however by spring germination is reasonable good. I also scarify the Arctostaphylos seed with a bonsai bite cutter, just enough to remove part of the hard endocarp, but not to the embryo.

This works well for me and I am very satisfied with the results.

[Robert]

The pictures you showed earlier of Manzanitas in pots appeal to the nurseryman and gardener alike!

Tim,

It is interesting that you mention this. Currently I am working on understanding the breeding system for the Genus. I believe that there is considerable potential within the Genus. In the past, chance seedlings (both wild and within gardens) were selected and cloned as garden varieties. This worked well, however it only skimmed the surface of the potential within the Genus. Most likely I am incorrect, but it appears that no one has ever done any systematic breeding with Arctostaphylos. Consistent and reliable seed germination is most likely an impediment. The flowers are small and not easy to work with (same with blueberries but this hasn't stopped blueberry breeding). So far I have observed that some species appear to be obligate out-breeders, i.e. they will not self or they do so with difficulty. There also appears to be two (maybe three) phylogentic lines within the Genus, an important consideration when breeding. Breeding for a high degree of resistance to Phytophthora would be helpful. Some of our native endemics, such as Arctostaphylos myrtifolia, are threatened with extinction due to Phytophthora in their native habitat. Just a few considerations. So it appears to me to be "the wide open spaces" with many directions to go with the Genus.

[fermi de Sousa]

The Toyon, Heteromeles arbutifolia, were looking exceptional with their bright red berries.
.......

Toyon seedlings - sown 18 Sept and 1st germination 16 October.
Should they be pricked out now or when they go dormant?
cheers
fermi

[Robert]

Toyon seedlings - sown 18 Sept and 1st germination 16 October.
Should they be pricked out now or when they go dormant?
cheers
fermi

Fermi,

I have good success pricking out Toyon seedlings at this stage, especially if the weather is not too hot. You might want to keep 1-2 seedlings in the seed pan in case something goes wrong. Once they get established in a liner pot, they will grow quickly and will benefit from being moved to the next size pot when ready. By autumn the plants could easily be 30-40 cm tall and be ready to plant out in the garden. Once established in the ground they will need little or no summer irrigation (they are tolerant of some summer irrigation). In their natural habitat they can be found in full sun or part shade. I like to give them a little bit of shade at the farm. Once they are established in the ground and are receiving less irrigation, they will grow very slowly. Older plants can be tidied up by being cut to the ground (they stump sprout after fires in their natural habitat). This is generally not necessary, but it is an option with a very old plant.

Good luck. The seedlings look great.     They are fairly easy-to-grow, at least here in California - not surprising.  I am here at the farm right now. If I have time (have to take my mother to the doctor) I will take a photograph of one of the plants on the property here.

[Tim Ingram]

I am sure there would be a great deal of horticultural interest in the Manzanitas Robert, especially plants that are resistant to Phytopthora and tolerant of more summer-moist climates. They are virtually unknown in cultivation in the UK but with a clear tendency to more Mediterranean-like weather in the south, as a result of climate change, they could become more amenable to cultivation. Ceanothus are so widely grown here that it is surprising that Arctostaphylos have not been trialed more.

Heteromeles arbutifolia looks interesting too; there is a striking picture of it in Nevin Smith's book 'Native Treasures', and he mentions a form 'Davis Gold', but says it has had little horticultural selection. Do you know this book Fermi? http://www.ucpress.edu/book.php?isbn=9780520244269

[Maggi Young]

Nevin Smith's book 'Native Treasures',  Do you know this book Fermi? http://www.ucpress.edu/book.php?isbn=9780520244269

Also available via  https://www.amazon.co.uk/d/Books/Native-Treasures-Gardening-Plants-California-Phyllis-Faber/0520244265/ref=sr_1_fkmr0_1?ie=UTF8&qid=1478885982&sr=8-1-fkmr0&keywords=Native+Treasures+Gardening+With+the+Plants+of+California+Nevin+Smith+%28Author%29

[David Nicholson]

Also available on ABE Books from a British seller, £20.78 included p7p

[Hoy]

I have only tried smoke on some Australian seeds once. The seeds germinated but I don't know whether it was the smoke!
Have to try your technique next time, Robert.

[Tim Ingram]

I have this foolish rush to the head about books every now and again and have a list as long as my arm gleaned from Amazon and http://www.nhbs.com! One I came across which has very good reviews is: 'The Californian Deserts - An Ecological Rediscovery' by Bruce M. Pavlik. I wonder if anyone has this or knows more? Another is 'Little Big Bend' (Trans Picos, Texas) by Ray Morey, which I do have. There is a fine detailed literature on the flora of the USA, another reason why Robert's adventures are so compelling.