Some interesting facts about Laurel Sumac and it's ability as an ideal nurse plant which utilizes Hydraulic Lift & Redistribution of sub-soil water which facilitated this Torrey Pine to thriveI've written previously about this specific location in El Cajon California on the famous Rattlesnake Mountain regarding the Torrey Pines planted there over 30+ years ago and the emotional response by many folks over the irresponsible actions by Sky Ranch Housing residents who cut them down with chainsaws and the blind eye stance by Center for Natural Lands Management to what took place even though the conservation area has a plethora of threatening signage around this mountain about the consequences of trepass into this conservation area (I would presume this also means Sky Ranch residents). I did contact someone at the CNLM (I don't remember his name), but he said there was nothing they could do. However this post isn't about them or the negative actions they undertook. This is for people who wish to understand why these trees succeeded in such an inhospitable environment for trees where failure should have been the norm. The practical applications I used so many years ago which were inspired of biomimicry (strictly replicating how Nature works) is even more important now in view of the major declines of Torrey Pines at their native habitat in La Jolla and Del Mar along the coast which I just now wrote about in this link below.
|My photograph from 2011|
This Torrey Pine tree above was one of many planted during the winter rainy season of 1980/81 after a wildfire had raged all across the Rattlesnake Mountain range between the cities of El Cajon, Santee and Lakeside that previous hot summer of 1980. I had planted other Torrey Pines during the 1977, but the wildfire of 1980 consumed all of them. It was in the middle 1970s when I was taking Ornamental Horticulture that some research was just coming out about the idea of nature having some plants which acted as nurse plants for tree seedlings. That intrigued me and my first experiments with testing for the best nurse plants were with California Buckwheat shrubs. While they worked okay, many plants failed after a couple of years and I eventually settled on Laurel Sumac which I found far more successful. I eventually chose the location I did because it was remote and rarely had visitors. It was on the direct south facing slopes of Rattlesnake Mountain towards direct sunlight. Not exactly an ideal location for trees in the dry west. Very little trails or reasons for people to hike around there. The tree in the photo above was over 25' in height when this photo was taken in 2011. It grew slowly at first, then started shooting up more as it matured. Under more ideal conditions it would be almost double that height like my 4 Torrey Pines I planted at my home in Anza California at elevation 4,500' (Table Mountain) back in 1986. Those trees are about 50', but the San Jacinto Mountains also get far more measurable rainfall per year compared to the interior hot valleys east of San Diego. An important part of that rain also comes in the form of Summer monsoonal thunderstorms from Mexico, something El Cajon never sees. This tree below is the smallest of the two Torrey Pines mainly because it became overwhelmed by it's nurse plant's foliage until it much later found a way out from the Laural Sumac's canopy. Hence you can see the crocked picturesque angle it had to take much like the Torrey Pines along the Sea cliffs.
|Photo is mine from 2011|
|Image - AZ Plant Lady|
|Photo is mine from|
(Research was tougher come by back in the 1970s as access was limited to conventional brick & Mortar libraries, school textbook references and subscriptions to journals. Today we have the internet which provides mountains of research on how nature works. And yet amazingly biomimicry still doesn't represent mainstream science.Human understanding of plant ecosystem mechanisms in the wild was improving in the late 70s - early 80s. I found the research of US Forest Service Biologist, Dr Donald Marx (former senior scientist for PHC), who was studying which was the best species of ectomycorrhzal fungi that would benefit new pine and oak seedlings for survival. His conclusion was Pisolithus tinctorius like the one I collected here in the photo above from the San Diego County backcountry just south of the gold mining town of Julian. So I figured why not. The dried puffball truffles which looked like dog turds had the dark brown powdery substance (spores) I needed to make this work. I dug small three inch deep holes (about four) around all sides of the Torrey Pine seedlings with my finger and drop in some of the chocolate coloured spore powder into the holes, then back fill it in with soil and watered. It was crude in comparision to what I use now because many of the commercially prepared mixes today come with root growth stimulators like humic acid, etc. These are important because they encourage new root hair growth which is necessary for the fungi to begin to colonize. The fungi will only colonize the root hair tips or cap when it comes into contact with the spore. I worked quickly because in 1982 I was moving to Idyllwild California up in the San Jacinto Mountains. Take note below of the benefits of fungi and plant root interactions.
A Perfectly Natural Phenomena of Older Needle Drop in Evergreens like Pines
|Image - affordabletrees.com|
|Photo: Ladd Livingston, Idaho Department of Lands, Bugwood.org|
Take note in the graphic above, it indicates two and a half years growth is still going strong. However, about three and a quarter years growth is being shed. In some cases this could also be due to drier, maybe even drought conditions. Hence the elimination of older needles may help limit transpiration surface to help the tree survive.
References on Dead or Dying seasonal Pine Needle Drop
Why the ability of Pine Trees to hold many growth years of their needles is important
|My last photograph taken 2013 - Tree was diliberately destroyed the following year 2014|
|Colorado State University|
|Image Google Earth (2914) - Interchange between Freeway 52 & I-15|
These pines are actually Torrey Pines planted along the western side of Interstate 15 heading south to San Diego just before the Freeway 52 interchange. Take close note of the extreme stress they are in holding only present years growth of pine needles and tiny needles at that. Torreys have some of the largest and longest needles of most pines. These are also natives and not that far from the coastline where they are native. This location also experiences a strong marine air influence of daily cloud cover, especially in May-Gray & June-Gloom periods. Still they are stressed more so than those Torrey Pines further east in the much hotter inland interior valleys of Santee, Lakeside & El Cajon. Not to mention the location on a southern slope face of Rattlesnake Mountain in direct intense sunlight. I should say that some of the Torrey Pine seedlings I did plant within the shelter of California Sagebrush and California Buckwheat did well for a few years, but at about 10 years they looked much like these example you see here above and below. Eventually they died or were vandalized by idiots with guns for target practice. Only the trees planted within Laurel Sumac fared exceptionally well. The installation plan and maintenance techniques are clear, Nature needs to be replicated through biomimicry. Now look at this same location below with a Google Earth shot in 2017.
|Google earth Same location along Interstate 15 (2017)|
Take note of the lusher greener plants in the foreground. In San Diego this past rainfall season they had much heavier rainfall records, but also an irrigation system and plants have been installed in the foreground. The trees are still in an incrediblly stressed out state with only present growth barely hanging on. Water is not the only key here, but rather colonization of Pisolithus tinctorius mycorrhizal fungi. PT mycorrhizal fungi is the best fungi for plants growing in hot dry areas. Yes, species does matter in this case. But so does a supprting cast of native deep rooted chaparral shrubs in the right strategic placements in this industrial landscape.
Supporting Cast Members in the Landscape, includes various species of Chaparral
|Photograph by David Magney (2005)|
|San Alijo Lagoon Conservancy|
"Laurel sumac roots are deep and extensive; vertical root depth of one individual in the Santa Monica Mountains exceeded 43.6 feet (13.2 m)"
One of the most amazing phenomena of a good nurse plant is it's deep root system ability to extract water from very deep subsoil layers and bring it to the surface. This process is known as Hydraulic Lift & Redistribution. Not only for itself, but also the more shallow rooted shrubs and perennials around it. But it's also beneficial for tree seedlings like oak or pine which would otherwise fail and not make it to the sapling stage of life and beyond towards being a fully mature tree. Especially at night will nurse plants like Laurel Sumac pull up incredible amounts of moisture for themselves and other plants as you see here on the left in the illustration. In places like Africa, plants like grasses and other forbes on the Savanna benefit by growing closest to those giant picturesque Acacia trees like Acacia tortilis. Young tree seedlings also benefit as a tiny emergent seedling from the nurse plant's shade before it pushes through the shrub's foliage when reaching for the sky on it's own. But there is so much more to this hydraulic movement of water.
There is yet another reverse type of phenomena known as Hydraulic Descent where in winter rainy season when the shrub or tree is dormant and not actively growing above ground, the root system is still active underground taking surface soils saturated with rainwater and sucking in and pumping that water into deeper sub-soil layers. If an ecosystem is healthy enough, this collective action by trees and shrubs can recharge acquifers. Many soils are to tough for water to percolate on it's own, so a healthy vegetated ecosystem like an old growth forest or even an old growth Chaparral Plant Community of Southern California will saturate the deeper layers of sub-soils for later usage during the hot summer months. Now even though this shrub is endomycorrhizal and will not form interconnected relationships with pines, oaks, etc, they will still release water from their lateral roots at the surface which can then be accessed by the ecto mycelium or fungal strands. When I lived at elevation 4,500' I used the chaparral shrub called Redshank or Ribbonwood as a nurse plant. Take a look at this gallery of trees below from my former acreage in Anza California.
|Photo Mine 2012|
These to Coulter Pines above and below were planted across from one another. These trees were foot high bareroot trees I planted on a remote section of my acreage in Anza California. No irrigation. Although these were wild collected from along roadsides, I still inoculated them with Pisolithus tinctorius or P.T. Mycorrhizal Fungal spores. I also located them next to Scrub Oaks or Redshank Chaparral Shrubs. If Redshank was unavailable then I would use it's cousin Chamise or Greasewood (shrub gets blamed for intense wildfires), both of which are also ectomycorrhizal, but under only certain environmental conditions like times of heavy rainfall years. This is important to know because such knowledge allows for foresters to plant trees like Jeffrey, Coulter or Torrey Pines to pioneer into predominantly chaparral areas. Thus the shrubs and trees can interconnect through the mycorrhizal network and young trees throughout youth will be assured of being hydrated by their chaparral nurse plants. Up in Anza the Parry Pinyon will interconnect with Chamise and redshank during the wetter years. Sadly the present property owner removed some of the chaparral around the trees and built this shed between them. Still the healthy start for these trees has been a success.
|Photo is Mine 2012|
The three trees below here are two Ponderosa and one Coulter Pine. The Coulter was actually a volunteer under a Redshank which was planted by a scrubjay from pine nuts taken from a large maturee tree next to my front porch. The two Ponderosas I planted within the same chaparral. At one time they were all surround by Redshank and Scrub Oaks, but the present owner wanted all brush removed. But notice on all my trees the five or six years growth of needles still on their whorls ? Very little leaf dander under these trees. This is a sign of very healthy trees. An odd side effect was that there was also an improvement in shrub vegetation and vigor after I inoculated with fungi, especially from the scrub oaks. Truffle formation was everywhere after that. The other fascinating thing here is that these trees are already baring pine cones.
|Photo Mine 2012|
Below are the three Torrey Pines I planted in Anza, California
|Photo Mine 2012|
These four Torrey Pines were planted on this bank behind the house in association with California Coffeeberry, San Gabriel Flannelbush and California Holly (Toyon). The year was 1985 where we has a couple of winters (3 in a row which had extremely low subzero temps from Arctic blasts from Canada and high wins at times from 50 to 60 mph. It was insane. The only problem for the Torreys were the very tips of all needles turned brown for about an inch in length. No problem, because after those three winters the central leader grew more than a meter or more in length, with often a secondary growth spurt after summer monsoonal thunderstorms which were intense with heavy rainfall. So no worries at high elevations and no supplementary watering after that.
Examples of Nurse Plant Mutualisms found in Nature within San Diego County
|Photo is mine from 2013|
The photo above shows a stand of Fremont Cottonwoods on the Henshaw Valley floor in northeast San Diego County. Take note that these large deeply rooted Cottonwood trees are able to support other smaller native plants like this wild native California Rose (Rosa californica) hedge. Other plants are also able to thrive under these trees like the native Snowberry (Symphoricarpos albus laevigatus) and Western Bracken Ferns. This location is amazing because of it's distance away from the forests on the mountainside and the fact that birds or animals originally brought the seeds of these plants to the trees through their feces droppings.
|Photo is mine from 2013|
This photo is much further east in the backcountry community of Ranchita where my brother lives. This is a much hotter drier area just before the landscape drops down into the Anza Borrego Desert. The tree is an Interior Live Oak and the plant below which it is supporting is the native Honeysuckle. Take this Oak tree away and the honeysuckle dies. The area is just too harsh and dry for it to thrive without a companion nurse plant. No doubt a bird flew within the foliage of this Oak tree, pooped after eating the honeysuckle fruits somewhere else and poof, a honeysuckle seedling.
|Photo is mine from 2013|
|Photo is by Cody Bish|
An Icon of the Old West, Sagebrush (Atermisia tridentata) is Still Demonized as a Competing Invasive in it's Own Native Habitat
Tragic End to one of the koolest 30+ year Forestry Nurse Plant Experiments I've ever accomplished in 2014
|Image taken from Google Earth|
|Image is mine from 2011|
San Diego Coast Cholla
|My photograph from 2011|
This photo above shows a different viewpoint on how close the Sky Ranch Housing Development came to the Torrey Pine experiment. In fact this is the same smaller Torrey Pine I posted above, but out of view of the housing. Sadly in 2014 these Sky Ranch home owners and I'm guessing with the blessing of the Conservation Area Biologist (I only say I'm guessing because he was very vague on the telephone when I called to report the incident and was disinterested in doing anything about the trespass and destruction), cut down with chainsaws all of these Torrey Pines. They were in their backyards and the wives ran into the house to get their husbands because i was photographing the area. The husbands weren't exactly overly friendly. The reason these residents gave me was that they were a fire hazard. The biologist in Escondido said they were non-natives to the Coastal Sage Scrub within this designated California Gnat Catcher Conservation Area. This was bunk, almost a century prior to this Rattlesnake Mountain being considered as a conservation area, no one ever gave a rat's backside about Rattlesnake Mountain. In fact the very landscape company they hired to restore areas damaged or disturbed by the Sky Ranch contractors installed numerous exotic non-native Mediterranean plants like Rock Rose, some type of Iris and a variety of other non-native cactus to this mountain. Friends and neighbours were upset for me, but frankly while I was bummed in the beginning, I had always understood the property was never mine and the trees could succum to whatever disaster came along, be it wildfire or housing development. In any event what cannot be taken away is the valuable experience and knowledge I gained from these nurse plant experiments. So seriously, nobody should hold anything against these folks. That's just the way our world works.
Gallery of Photographs Documenting the Destruction of the Torrey Pines
|Photo is mine 2014|
|Photo is mine 2014|
|Photo is mine 2014|
|Photo is mine 2014|
|Photo is mine from 2014|
http://www.eccalifornian.com/article/exploring-breathtaking-beauty-rattlesnake-mountain-habitat-preserveAlso another news source, inewsource.org, had an interesting article from September of 2016 about the dire situation of all forests within Son Diego county disappearing for good.
An Urban Landscape Success Story at the foot of Rattlesnake Mountain's Sky Ranch Housing Development
|Image Mine in September 2015|
Further Educational References on Practical Applications Biomimicing Nature
My source for mycorrhizal fungi mixes http://mycorrhizae.com