Why won't fruit trees grow in Cascades foothills?

Hi,
I am lucky to have spent my summers in the countryside in Europe, so I have a bit of knowledge and a lot of love for trees, forest and of course fruit.
So five years ago I bought a small piece of land in the foothills of Cascades (1400 ft altitude).
The land was covered with 10 year old Douglas fir but there were a couple of large open areas. So I choose one of them to try to create an orchard in the woods. The problem is almost no fruit tree survives/grows. Here are some facts to understand my predicament:

On the plus side, the soil is 6ft deep well drained and very good (volcanic ash plus silt). The land is sloping south and west and there is plenty of sun. The poplars, alders, vine maples, maples, black cherries etc grow like crazy. The ground was covered with dead wood, ferns and brambles but I threw some grass seed around and now the grass grows 6 feet and stays green through the summer.

On the other hand, there are elks and deers passing through spring and fall and they do a bit of damage, even though I spray with stinky repellant found online. There are also a lot of hares and ants around (I don't see any damage though). The nights can be cold even in the summer and there are harsh changes from day to night. There is also 70" of rain mostly in the winter.

I planted a lot of fruit trees on this ~1acre open space and here are the results up to now:
Dead or dying: peach, nectarine, pears (asian and european), paw-paw, plums, apples, mulberries
Stagnating: cherry, quince,
Ok for now: Chestnuts, walnut, hazelnuts
Growing great: black locust, willow, goumi (even though one was eaten to the ground, the others are good!)


Any suggestions, ideas on what I can do to help the fruit trees survive?
I had fruit trees dying with no sign of leaves/branches being eaten by the deer. The pears/apples seem to get some disease - their leaves get dark spots.
What can I plant as ground cover to help?

Thanks!

I'm just starting out with fruit and nut trees myself so can't offer any expertise, but there are two local tree nurseries that might be able to offer some advice and both places employ some permaculture practices - Raintree Nursery in Morton, WA and Burnt Ridge Nursery in Onalaska. Good luck!

Just a few loose ideas:
Dig up one or more of the dying trees and give the roots and root zone a close look. Gophers and even termites are capable of damaging roots enough to kill a young tree. Most of my important plants get put in chicken wire baskets sunk in to the ground because of the gophers.
Go on a driving tour of your area, especially focusing on areas of similar altitude, aspect (west facing? south facing? etc.) and climate. Spring is a good time to judge this because plants will be leafing out or in bloom at the same time as where you are, whereas a slight difference in microclimate and they will be advanced or delayed. Pay attention to what kinds of fruit trees are growing in these zones.....even down to varieties if you can get this information, and use this as a guideline for your plantings. The West is a land of many microclimates and a ten-mile drive can put you into a completely different zone, therefore regional recommendations, especially from commercial sources who have a vested interest in selling you plants, are not to be trusted unless backed up by independent research.

I'm concerned that your apples and pears are failing. There are blights that cause issues but we have a great climate for both. Cherries should be easy and if blacks are working I'd say they like the acid. I'd do some soil tests and see if you have something funky going on. Peaches grow in Oregon to 1000 feet with no problems, 1400 feet shouldn't effect the tree just the output. Doug fir isn't as harsh as pine but old growth can have some long term acid effect.

How close are your walnuts and other alliopathic trees from the others? I was wondering why a spot was doing poorly and realized a tree nearby that I had yet to ID was a walnut. On that note, anyone know plants that go ok with walnuts besides other nuts and mulberries?

How's it going? What side on you on? We're in the foothills as well and we have great success with fruit trees (well, our neighbors did ours are only 2nd year). Have you checked the PH? Our soil is  very acidic in areas where cedars, firs do well with huckleberries, blueberries, rhodies and camellias. Where we planted our orchard we brought in about 35 yards of mulch (free from the arborist) and a couple yards of manure/ compost. Might add a little lime this spring depending on how it reads out.

I would think of a soil problem. Have you a clou about the ground water table fluctuations during a year ? Anyway, i have had (in Europe) similar problems with sage. It did nog thrive at all.untill i got seeds from a variety growing at my moms garden. Plants from those seeds doe wel. If you have a rootvariety that does not do well in your soil perhaps you should look at selecting a rootstock before you plant an orchard ?

My sister is in the foothills (west side, up above Monroe, WA) and the only fruit trees that do anything for her are plums. Her apple and pear don't blow her mind with their yields. She's thinking something allelopathic might be to blame, but she hasn't found it yet.