adunca, the idea that trees compete for water is a question that needs discussing as the
permaculture methods are those of planting a mixture of plants, as Geof Lawton says, he planted a lot of plants that weren't fruit producing in his desert
permaculture garden to the suprise of the Jordanians, probably mostly ones that had m¡nitrogen fixing nodules on their roots.
In decorative gardening they plant strange groups of trees sucessfully and when we grow food we suddenly decide we can't do what flower gardeners do all the time.
Junipers are prefumed trees, an insence bearing tree, their wood is good against insects full of things that put off insects. Oil from the oxycedrusonr type of juniper is good against nitsand mange mange for example, it is also used in imbalming people, this is proof of their force against insects and other pests. Junipers planted among your fruit trees may reduce the amount of insects that find your fruit trees.
The idea that plants compete for nutrients has one very negative outcome, which is that plants are left as and island of green in the middle of a large emppty space, the competition for nutrients and water is so reduced but so is the shade, of the area, and so are the amount of plants contributing vegetable matter to the soil, vegetable matter that first coverst the ground protectings the soil from the rays of the sun and stoping the water in the soil escaping as it taps the earth a bit and later as it rots down and forms part of the soil is what provides nitrogen and what absorbes and retains water more than soils without a lot of vegetable matter could do. Trying to increase the chances of evergreen oaks say, by reducing competition from other plants, is what has lead to very poor soils in many places full of evergreen oaks. The resulting poverty of the soil is probably what has made these trees so on the edge of disaster that they are drying up from any chance illness. NOrmal undernourishment leads to reduced resistance to illnesses. The prescence of live stock in a small enclosure at the feet of evergreen oaks also seems to kill them, they dont like too many nutrients but there must be a too few as well.
Trees and bushes do something called hydraulic redistribuñtion, their tap roots feed their drying superficial roots with water in a drought and if there is a
shower of rain this movement of water from the tap roots to the superficial roots that run horizontally just below the soil is immediatley reversed and the superficial roots take up water which is taken down into the soil through the tap roots and stored at a depth.
That trees supply their superficial roots with water means that there is more water just below trees in a drought, and so the grass can stay green at their feet when it has already dried on other bits of ground.
In spain the dehesas of junipers, juniperus thurifers, juniper farms are a sylvo pastoral exploitation. The trees trunks make very good hard beams and posts for the construction of dwellings and the ground at their feet is used to pasture sheep and goats. The dehesas of junipers are where sheep and goats are farmed while dehessas of evergreen oaks are where cows, horses and pigs, are kept. i woudl not take them out of a poor desert place at least untill I had grown something to take their place as they might be the only thing that will grow there.
The wood of the junipers is also used for fire wood, i have often smelt if being burnt in the village though that may well have been the old beams from a house that had been modernised that was being burnt. THe smokle of junipers is perfun¡med i knew a man in england who used to keep a branch of juniper in the fire place and burn the end a bit when he wanted to perfume his room.
The juniperous thurifera of dehesas, grow next to evergreen oaks and the evergreen oaks loook perfectly healthy when they grow nect to junipers.
I read a study about how it was proved that junipers take up through their leaves, the water of a summer
shower to light to seep into the ground and so likely to merely evaporate off the ground, so they are a good way of making sure you dont lose any rain water. A heavier shower is likely to run off the
land as dry ground does not take up water easily unless you have small dips on the ground that hold the water for a few hours, we tend to even out all ground and so reduce the places were it would make small puddles in a storm and increase the run off. I htink dottign small hollows around on your land should serve in the same sort of way swales serve in.
Junipers the oxycedrus at anyrate, are very hardy, dry country, poor soil trees ,very goood for the borders of deserts, Jesus Charco in Bosques del mediteranea y norte
de africa, biodiversidad y la luch contra desertification, says they spring up in the green belts that have been planted in the north of africa, of pino carrascal i suppose, if these are untended. Their berries are sweet and ripen in winter and feed the fauna and even live stock so if you want to reduce the desert they are a potential ally.
Junipers in the mountains of Guadalajara grow very close together were they have not been thinned out,thinning them out is a fire reducing ativity. and were the ground has not been poisoned with herbicides. Grass grows at their feet, so it does nt seem that they take up so much water as to stop other junipers or the grass growing the grass wont grow under beeches there leaves have a substance in the that ih¡'nhibite the growth of other plants.
On the other hand it may be true they take water from other plants.
I have had difficulty establishing plants near the elms that come up on my land, though wild plums grow next to them. I have had difficulties the only time i tried it, difficulties in one place is not conclusive evidence i suppose.
Maybe you only have difficulties if you plant somethign near a more establishe dtree till the plants establish a good
root system of their own.
One contributer on the bit of the forum that was talking about fruit trees and the fact that you should not plant an apple were you have just taken one out, the fact that they produce a substance that stops another tree from growing where an apple or rose has grown and said that if your plant has a
deep roots that it will survive being near another fruit tree, the bad effect mentioned only effects plants that are shallow rooted or have not grown their roots yet.
I have written a long peice on junipers in the woodland care section, that might be a help for ian, my garden is among hills covered in junipers in many placces and so i have read up about them. agri rose macaskie.