Doug Hack

Doug Hack wrote:Today I collected 400 wild bitter almond seeds in a bucket and planted them about every two feet along about 800 feet of perimeter fencing.  If even 5 percent of them survive I will have 20 new trees to start my hedgerow/shelter fence.  This took about four hours.

Update from this "planting" of four years ago.  There are two surviving trees - about three feet high.  They have been totally neglected for four years.  The very low survival rate I attribute to two things - 1) I did not actually put the seed into the ground, but just put it against the ground or slightly into the surface under a layer of duff. 2) The following Winter was one of the driest on record - less than 10 inches of rain total.  I feel like I 'wasted' 400 almond seeds.

If I had repeated this experiment with putting the seeds 2-3 inches into the ground I am sure the survival rate would have been much higher.  This would protected the seeds from drying before and in between rains, and also given the seeds some protection from mice.  If I had repeated the experiment each year I am sure the results would have been dramatically higher as this past Winter was one of the wettest on record.  There is no predicting the rains, but consistency will eventually pay off.

In the meantime I have had excellent germination rates planting in 1 gallon pots and have planted out several almond trees (some now grafted, some yet to be).  This is far more time consuming than just planting seeds.  An in-between level of inputs with a high probability of sucess might be planting three seeds in a selected spot and then watering that spot until the rains actually start to keep the ground moist.  

Here are some observations and thoughts about nitrogen-fixing plants:  I have tried planting from seed a variety of clovers, trefoil, vetch and alfalfa.  While all sprouted and grew for a while, only purple vetch has persisted and reseeded itself to a reasonable degree over years without attention.  It likes to grow on my woven-wire fences, and persists in patches even in areas mostly dominated by tall annual grasses.  All of the others needed management (mowing or grazing) and irrigation to persist more than one season.  

I have decades of experience with Black Locust trees and I feel they are very valuable as a pioneer soil-improvement tree.  Their roots fill the soil over a wide area (up to three or four times the drip line diameter) and they provide plenty of extra nitrogen for other plants.  When water stressed in Summer they drop leaves which increases the amount of light for plants under the shade canopy.  With regular irrigation a lush lawn will grow under them with no other fertilizer.  In my climate most plants grow better under them than in full sun.  They are tough and will survive with no irrigation once established a year or two, but growth will be very slow and they will drop nearly all leaves in the summer.  If they are grown large with irrigation, and irrigation is stopped, they will die back substantially, looking very bad, but surviving.  They have lots of root sprouts and will create thick colonies if allowed to.  In my soil (which is shallow and light over thick hardpan) they are unable to sink roots and usually blow over after a few decades.  This probably wouldn't be a problem in deeper soils or where allowed to grow very thickly.

I have limited experience with albizia julibrissin (Mimosa or Silk Tree), but I like it very much and it has some advantages over Black Locust.  For starters it does not have sharp thorns.  It provides an even lighter shade than Black Locust and it will fold it's leaves to save water.  It seems to be almost un-killable, fixes substantial nitrogen and (once well established) drops a thick litter of flowers, leaves and seedpods which is an advantage for soil development and a serious disadvantage for manicured yards and patios.  The wood decomposes much faster than Black Locust which makes it more useful for chop and drop or any use for decomposing biomass such as hugelkultur.  It is a smaller tree at maturity but grows reasonably fast.  I haven't noticed colonies of root sprouts (although it resprouts when coppiced).  In my climate neither tree is likely to self seed.  Both create relatively small seeds with hard seed coats that need scarification and a moist environment to survive and establish.  I've had great success by pouring boiling water over the seed and planting those that have swollen up 24 hours later.  I am planting Silk Trees in between my fruit and nut trees as nitrogen sources and soil improvers.  If they ever get too competitive I will cut them back and use the cuttings as mulch.  

I have tried Siberian Pea Tree (or shrub) but it doesn't seem to like the climate here (USDA Zone 9B).  It may be too hot for it.

I have also tried Arizona Mesquite.  Hand sowing seed into annual grass land did not sprout/survive.  Scarification and growing in pots was very successful, but the trees do not seem to thrive once planted out.  Maybe my winters are too wet for them?  The growth is extremely slow compared with either Black Locust or Silk Tree.  I'm not impressed but they may have potential for even hotter and drier climates than mine.  

As a shrub I have had good success growing a variety of Ceanothus Arboreous (Owlswood Blue) which is considered to be a nitrogen-fixing plant.  I have propagated it from semi-hardwood cuttings (somewhat difficult).  It has grown and survived well and seems to get by with a minimum of summer water.  I haven't let any go unwatered and I have doubts that it would do well here without some help in the Summer.  It has large green leaves that deer, goats and sheep like to eat.  It also has beautiful blue flowers in Spring that the bees love.  I'm not sure how much nitrogen it actually fixes (it stays very green and grows reasonably fast in poor soil) or shares with other plants.  

Not on any list of nitrogen fixing plants is Mulberry.  However I have observed it growing amazingly fast and green with very high protein leaves on poor soil.  I cannot believe it could possibly do that without fixing nitrogen somehow.  I have collected several varieties and I highly recommend them as a pioneer tree.  The branches and leaves can be chop and dropped.  The fruit is variable but many varieties are very good to eat - and birds love all types!  My mulberries keep the birds so well fed that they mostly leave my cherries alone.  You can feed the leaves to ruminants (sheep love it!) and chickens.  I have propagated it from cuttings, transplanted bird dropped seedlings and grafted it.  My observations are that in a hot climate it should be left un-pruned to grow low and wide - shading as much of it's own root zone to the ground as possible.  This also makes the fruit easier to reach.   The roots are very vigorous and spreading and develop sinkers that I suspect are getting through my hardpan after a few years.

The figs I have propagated from cuttings seem to need a lot of water and haven't produced much fruit yet.  I suspect they are not the best adapted to getting by on their own in a hot climate.  

I've planted a lot of different varieties of pomegranates (easy from cuttings) and they seem to do very well here.  Mine are still very young and I don't know how much water they will need to fruit, but they seem very promising.  

I have also planted a lot of varieties of table grapes from cuttings and I am very pleased with the quantity and quality of fruit they produce.  They do need to be watered to produce, but they grow very fast, producing lots of leaves (Thompson Seedless leaves are edible), and biomass every year.  

My more traditional orchard is doing okay, but it is water-intensive and so far not impressive.  This Fall I will collect as many Silk Tree seeds as I can find and start trees to interplant thickly with the fruit trees.  I think the extra ground shade and nitrogen will help in three or four years.

Here are notes from my recent on-line research into seed germination:


Short simple explanation of stratification and dormancy.

http://www.ces.ncsu.edu/depts/hort/hil/hil-8704.html


Wikipedia has a technical listing of the many varieties and combinations of

seed dormancy. Although comprehensive, it is likely to intimidate the reader

and does not include useful techniques and applications for breaking dormancy.

http://en.wikipedia.org/wiki/Seed_dormancy

This article from the Montana State University is packed with specific

practical advice by species for collecting, storing, and germinating seeds of

many common temperate trees and shrubs.

http://csfs.colostate.edu/pdfs/growseed.pdf


Here is a link to a 1960 article on seed propagation of woody plants by the

Arnold Arboreatum of Harvard University that is often referred to in later

literature, but contains instructions and explanations not found elsewhere.

http://arnoldia.arboretum.harvard.edu/pdf/articles/1553.pdf

Chapter 9 of This 1985 FAO Guide to Forest Seed Handling details various

methods for breaking seed dormancy (including batch processing of large

quantities), although containing only minimal reference to species

applicability. Notable is a chart showing the effect of germination on Black

Locust (Robinia Psuedoacacia) of various pre-treatments. Sanding the seedcoat

produced over 70 percent germination in less than 10 days compared with 10 to

14 percent in 12 to 40 days without treatment. Other sources state that this

species has no stratification requirements and has only simple seedcoat

dormancy. http://www.fao.org/docrep/006/AD232E/AD232E00.htm#TOC

Some varieties of nut tree seeds (specifically oaks and walnuts) should never

be allowed to dry out thoroughly after ripening.

Soil germination tips for a variety of tropical fruit, ornamental, perennial,

heb and vegetable seeds from Trade Winds Fruit:

http://www.tradewindsfruit.com/seed_germination_tips.htm

Germination Characteristics of South African Tree Species:

http://www.worldagroforestry.org/downloads/publications/PDFs/ja07164.pdf

Germination experimental study for Common Elderberry (Sambucus Nigra) Warm

stratification for 60 days followed by cold stratification for 90 days gave

nearly the same results as acid scarification followed by 90 days cold

stratification. Mechanical scarification was not included in the study.:

http://www.plant-materials.nrcs.usda.gov/pubs/mipmctn10584.pdf

I recently found two authoritative sources that said Black Locust seeds don't need a low temperature stratification, but they do need a seed coat scarification - perhaps with sandpaper. Germination was greatly increased and reduced to under 10 days after two hours in a specialized drum sander. Hand sanding should work.

All of the volunteer figs here were passed through the intestines of birds, and landed where extra water (and shade) was available. I share your doubts about their ability to sprout and survive with no help in a mediterranean climate. However, they are an excellent food tree given a reasonable amount of irrigation.

Here is a very similar study (with similar results) using the species Juglans major (Arizona Black Walnut). On this site, the tree's roots had penetrated a cemented hardpan layer. http://www.blueplanetbiomes.org/velvet_mesquite.htm

The reason I find these studies so important, is that my property and major portions of the east side of the Calfornia central valley are underlain with cemented hardpan. This means that even the meager seasonal rain that falls, rapidly saturates the shallow sandy surface soils (often only 12 inches deep) and runs off. Even when surface runoff is not apparent, there is significant sub-surface drainage leaving the higher areas to dry rapidly, and the lower areas to be saturated for an extended period - drowning the roots of many species.

I have read with interest the discussions of hugelculture and imagined cutting deep trenches along the contours and filling them with moisture retaining wood. There are several problems with this concept: First it is prohibitively expensive in terms of equipment rental and time. Secondly, the fragile topsoils will be substantially destroyed in the process. There are other reasons, including an intuitive one that this sort of land raping is immoral and exactly the opposite of good permaculture practice.

These studies show that there exist at least some (perhaps many) tree species with root systems that will grow water storage in place without resorting to heavy equipment and fossil fuel consumption. If the roots penetrate the cemented hardpan and store water in the relatively porous layers of sediment below, they will be capturing and storing the seasonal rainfall for extended use. They may also reach acquifers with significant ground water. The earliest well in this neighborhood that I am familiar with was hand dug (pickaxed) through the hardpan and produced water at about 20 feet. Later wells were drilled to 50-80 feet and produced substantial irrigation water. These layers were 'used up' and domestic wells in the area are now at the 120 to 160 foot level. Tree roots might still find substantial usable water in the higher levels of sediments, as their usage would be slower than an electric pump.

There is one oak tree on my property that grew in dry grass far from any irrigation. It became established within the past 40 years, and is now approaching 40 feet tall with a diameter about 14 inches. I have never seen it produce acorns. This tree stays green and healthy looking all summer, with no irrigation. Based on its leaves, it is most likely a California "Valley Oak" (Quercus lobata). These typically grow in deep valley soils, often near water courses and require a good soil water supply. I have to assume that it has successfully sent it's roots through the hardpan and is tapping deeper water sources. There is no way that a tree of its present size could maintain such a large leaf canopy without access to lower level water. This indicates that tap root penetration of the thick hardpan is possible. Having attempted to transplant oak seedlings (California black oak Quercus kelloggi) that I had planted in a vegetable bed, I know that Oaks with only two leaves have already sent a tap root down deeper than I could dig. There is probably great potential for arid land reforestation in many oak species.

I have a correction. The Bay Laurel tree I mentioned before does not fit the description of a California Bay, it appears to be a true Bay Laurel (Laurus nobilis) originally native to the Mediterranean. This one is adjacent to watered lawn, so I'm not sure how they do in dry land. My neighbor appears to have several that were planted by birds (under a dead tree) and established when his lawn was watered. They are still surviving (with very yellow leaves) now that area is not watered.

Another species that may have potential for reforestation and food is fig. I don't have any on my property yet, but on what was my Grandparent's land there is a fig tree that is over 60 years old. Over the years the birds have "planted" several trees from this beginning. They only get started here with a little extra water (adjacent to the lawn or under roof runoff) but they are tough and get by with a minimum of summer water and no specific attention. These are what we call "Black Mission Figs" in California. They are supposedly descendants of figs brought to California 300 years ago by Spanish missionaries. This type of fig doesn't require wasps to fertilize, and they produce two crops (early and late summer). They are very sweet and delicious. They may require some irrigation to get a crop.

Here is a link to a description of arid and sem-arid climates that provides a framework for understanding: arid climates

I read an article (that I can't re-find) suggesting that tree canopies in the San Joaquin Valley of California may effectively double the 'rainfall' under the canopies by condensing common winter ground fogs and nightly re-condensing a portion of transpired moisture. The average precipitation is 5 inches per year. Increasing this to 10 inches per year under the canopy is substantial.

Here is a scientific study of "hydraulic redistribution" (HR) by velvet mesquite tree (Prosopis velutina) roots. This species is a legume that produces edible seeds. The study shows that water in relative abundance in surface layers during periods of precipitation is redistributed by the roots deep into the soil for later use in drier periods. A portion of this water may become indirectly usable by other closely associated plants. The implications of this is extremely important. In our meditteranean grasslands dominated by shallow rooted annual grasses that sprout, consume all the available surface water, reproduce, and dry out there would be no HR. Introducing appropriate deep rooted tree species in correct densities for conditions could change the environment for other plants substantially. Avoiding getting bogged down in the technical details, mathematics, and assumptions of this study, it provides clear evidence of HR from surface lateral roots to deep tap roots during times when surface soils have a surplus of moisture. This is on soils that are far from ground water and are otherwise dry. A significant portion of this 'banked' water is available to extend the active period of the tree once surface moisture is depleted. This has important implications for the importance of tap roots (and possibly 'sinker' roots) in trees and shrubs for arid and semi-arid regions even where there is no significant sub-soil water to tap.

Link to a good description of velvet mesquite.

This is a very good time of year (in the Northern temperate zones) for this discussion as most vegetation is ripening its seeds. In addition to spreading the almond seeds around, I am collecting and redistributing seeds from Chinese Pistache (an 'ornamental') and Western Hackberry (Celtis Reticulata), both of which I have growing on my property, and which are doing well with little or no watering. In my area the Pistache is very commonly planted as a street or parking lot tree. They produce copious amounts of small seeds that birds eat, and they do well on a minimum of water and fertility. In areas with more rainfall they can become invasive.

The Western Hackberry is a 'native' that is also sometimes available from nurseries. The one I have was imported by birds, washed into a crack in an old concrete foundation, and has survived there for about 15 years - now a very nicely shaped small tree (about 15 feet tall) that has never had any attention whatsoever. One of its common names is "Douglas Hackberry", which I find amusing since my real name is Douglas Hack. The seeds of the Hackberry were used as food by native americans.

I have also taken about 50 tip cuttings of semi-hardwood from my ceanothus bush (California native nitrogen fixer) and inserted them into a large planter full of peat moss and perlite in the shade of my grape arbor. This is not a controlled rooting situation, but some may develop roots to be transplanted out. I also placed some cuttings from a California Bay tree that has survived over 60 years on my property from a volunteer. This is a small evergreen multi-stemmed tree that I could use as a privacy screen along the road. I have transplanted several root sprouts from my black locust trees, and will be continuing to do so as new sprouts come up.

I've been thinking about other free sources of seeds and plant material. My neighbor has an established olive tree that overhangs the street and is never picked - I will keep an eye on it for when the olives ripen. Another neighbor has a California Black Walnut tree, that he never harvests from. I know of areas in the foothills where black oaks and grey pines (both edible) drop their seeds along the highway. I've been saving the seeds from the fruit I eat and placing them in the area I've designated for a 'food forest'.

On a slightly different subject, I have also divided a five year old clump of bamboo (Bambusa Multiplex) , and planted it out as a hedge/windbreak for my vegetable garden. One clump about three feet in diameter has made about 40 feet of hedge spaced 18 inches. I don't know how little water it would get by with (it was in a shaded planting border with drip irrigation) but bamboo is pretty tough. This variety is small but supposedly edible, so once it is re-established I will harvest the shoots to control its spread. (or continue to divide it and establish new clumps in various places.) It makes useful poles about 1.5 inches in diameter.

I'm in Zone 9 just North of Sacramento in the valley. You don't say what your water supply is. Horses need either a substantial amount of unimproved pasture (five acres+ each if unimproved and not-irrigated) or a couple of acres of improved, irrigated, fertilized pasture, or a whole lot of money spent at the feed store. To my way of thinking, horses don't really fit into permaculture, unless they are work horses and you have LOTS of acreage. Horses also have problems with plants that sheep and goats thrive on. Starthistle comes to mind - as it has invaded almost everywhere in Northern California. If your future horse pasture is knee deep in starthistle, start with sheep and goats - they won't exterminate it (the seeds last in the soil at least five years), but they will get it down to a manageable level (although possibly still not safe for horses).

I have no budget to buy a lot of plants, and even seeds can add up. Lately, I've been looking for native plants (or well adapted imports) that are producing seed - and collecting it for free. There are LOTS of ceonothus and mountain mahogany in the foothills. They survive on essentially no extra water, and many of the ceonothus fix nitrogen, and if the deer don't get them first - supply good browse for sheep and goats. Your land may already have several established plants to get seeds from. Grey Pine (Digger Pine), and black oak are native and produce food for humans.

An exotic that can help forest your land (and feed birds) is chinese pistache. These trees are used in planting strips and parking lots commonly - and are covered in seeds at this time of year. Harder to find, but native is Western Hackberry, which also survives with little water and feeds birds.

Today I collected 400 wild bitter almond seeds in a bucket and planted them about every two feet along about 800 feet of perimeter fencing. If even 5 percent of them survive I will have 20 new trees to start my hedgerow/shelter fence. This took about four hours.

In the process of planting them I found a two foot tall volunteer almond, a one foot mulberry, and several tiny oak seedlings that I didn't know about. Trees in grassland! When the fires are controlled and grazing animals fenced out trees can get established.

I also planted sweet almonds in seven locations, with three seeds in each location. I just used a shovel sideways to skim the young wild grasses and duff away in about a two foot circle, planted the seeds shallowly, and pulled the duff back over them. This is in an area with existing Black Locust overstory and is being watered this Fall to establish new plants before the Winter rains come. I will report on the outcome of these low-input plantings.

Link to research on the root structures of various almond cultivars: http://www.actahort.org/members/showpdf?booknrarnr=373_13 There appears to be considerable variation on the degree of tap rooting versus fiberous rooting between cultivars.

I read quotes from one California almond grower who was very proud of a 2,000 pound per acre crop from a "fifth leaf" (young) almond orchard planted at nearly 120 trees per acre. He said that it took four acre-feet of water to produce a crop! He was paying $100 per acre-foot for water and apparently flood irrigating. Apparently the land was located next to a huge irrigation canal. Some California orchards are installing drip irrigation.

Considering the shortage of summer water thoughout the areas with mediterranean climates, I am interested in establishing orchard trees on their own roots (or planted in-place seedling roots) whenever possible, with the hope that a minimum amount of summer drip irrigation will sustain production. The current state of commercial orchard production (in California) requires extensive irrigation and water is transported hundreds of miles through huge irrigation canals from the Sierra Mountains to irrigated valley crops. Deep water wells are being used for many other crops, pumping "fossil" water supplies out of deep acquifers (often below sea level) at rates much higher than recharge. This is resulting in salinization of acquifers near the ocean.

Detailed discussion of world-wide commercial almond production rootstocks and cultivars:
http://ressources.ciheam.org/om/pdf/a94/00801305.pdf

Here is a very interesting quote from the above paper: "s. Due to the nonirrigated conditions of most Mediterranean orchards, almond seedlings had been the dominant
rootstock for centuries, because of their deep growth and associated efficiency for mining
nutrients and water. Often unselected rootstocks, even bitter almonds, were used for producing
seedlings rootstocks although later some efforts were directed toward some seedling lines
because of their homogeneity (Felipe, 1989) or resistance to nematodes (Kochba and SpiegelRoy, 1976). More recently, peach × almond hybrids are showing promising performance under
non-irrigation, due, in part, to the loss of the deeply mining almond tap-root when transplanting
(Kester and Grasselly, 1987; Felipe, 2000). 'GF-677' has been the most utilized rootstock in the
past years, with an increasing utilization now of new releases. "

Check page 28 of this University of California, Davis publication for a brief history and present direction of Almond bredding in California: http://sbc.ucdavis.edu/files2/57360.pdf

Clearly research for the commercial industry is emphasizing self-fertility first (because of bee pollinator availability problems and expense) and (secondly) either later bloom, or improved pollination source cultivars for the huge numbers of established orchards.

While self-fertility and later bloom both have potential for permaculture applications, it is unlikely that there is any major research being done to select cultivars for low maintenance applications. Commercial orchards (at least in California) use irrigation, weed suppression (cultivation or chemical), fertilization (with expensive tissue analysis), imported bee colonies, pesticides and very high mono-culture planting densities. The emphasis is on maximizing crop weight per acre.

For permaculture applications seedling cultivars are needed that can establish and produce on low-fertility marginal sites with minimum inputs. While current commercial research is not necessarily counter the needs of permaculture, neither is it directly applicable.

Today I will knock at least a hundred almonds from the tough bitter almond volunteers in my neighborhood, and toss them into high dry grass along the fencelines of my property where they will either sprout and survive, or not. If this is a good year for rains, some will survive (based on past volunteerism here). As they become visible in the grass, I will mark them with stakes and encourage them with once per month watering during the dryest months.

This book provides an interesting read not only about almonds, but several other major nut crops: http://books.google.com/books?id=7CK8LFCcvtcC&pg=PA9&lpg=PA9&dq=roots+%22almond+seedlings%22&source=bl&ots=PWEHprqgYr&sig=qfKnMFmQociFxXf-JQzMKwZRqW8&hl=en#v=onepage&q=roots%20%22almond%20seedlings%22&f=false