Forest Garden in wet clay?

Howdy everyone.
I'm trying to convert an apple orchard and the surrounding to a forest garden, in northwest washington. The site is on heavy clay soils, such that just downhill from the apple trees there's some very wet soil with standing water at various points in the winter. Black walnuts grow there fine, but many other trees have died in that soil (like 60 chestnuts, many years ago). In addition to the clay, the site catches all the water that has traveled underground from whatever soaks through the banks of a stream a few hundred meters up. It's not quite coastal, being some 20 miles east of the coast (east of Bellingham), and also is nestled next to a mountain, so the late afternoon sun is lost. We get cold temperatures ranging down to about 0-10°F for brief stretches in the wintertime, and sometimes a foot or so of snow.

While I've read a lot about Food Forests, I have little direct experience with them. A couple of things I'm wondering are:
• What would be good to grow around/under the apple trees to help them fight off the various diseases they have? Good guilds for apples?
• Is there much in the way of plants that would create a food forest or at least edible landscape in the boggy areas? Being clay, the do dry out considerably in the summer, so it's not a true wetland site, but whatever lives there will have to tolerate having its feet underwater for several weeks in wintertime.
• Failing this, is it possible to do hugelkulture/raised beds to lift some of these plants up out of the wet zone at least a little bit? I'm assuming that while they might survive, they'd never do very well if they get waterlogged as soon as the roots start digging too deep, but I could be wrong…

Any tips, experience, things to consider… methods, plants, etc., would be very appreciated. Thanks!

I'm on the other side of the country, but it sounds like our zone/sites/soils are largely similar (except I've had no luck with Apples, so I'll be no help there). Black walnuts also make up a significant portion of the woodland around me.

I'm only a few years in on my property, so I can't claim much from personal experience, but I'm on much the same quest and I will share the following:

I've got a lot of Honeylocust trees on the property, and I'll be introducing a large number of Black Locust in a few weeks. They are supposed to be good friends with Black Walnuts, and are great multi-purpose trees.

There are a fair number of maples and a few sycamores along the back of my property where it is positively swampy/waterlogged for at least part of the year.

I have looked into other useful tree species that can tolerate wet heavy soils: Swamp Oak, Sassafrass, Willows, Paw Paw, Ironwood, Grey Birch, River Birch, and some others. I recently found a list from the early 19th century of the trees most commonly found in my area and am utilizing that as a starting point.

I'm actually going to try some chestnuts this year, but will be planting them in the least-boggy place in the woodlot in the hopes of giving them a fighting chance.

Found this:

http://www.extension.umn.edu/yardandgarden/ygbriefs/h-claytrees.html

and this:

http://www.douggreensgarden.com/best-trees-and-shrubs-for-clay.html

Could you dig out an area below the apples into a pond to help drain the soil? Bill Mollison recommended 15% land be water. And yeah there are a lot of plants you can plant around apple trees to help, but they are one of the less disease resistant trees out there, so it'll take more work. To attract beneficial insects you'll want a lot of big flower heads with small flowers, for instance, everything in the carrot family, everything in the onion family, everything in the aster family, elderflowers... ect.

Are there any salmonberries, thimbleberries or devils club nearby? These are all boggy lovers, and have value.

Alders might also be a good choice to help rehabilitate the clay soils and survive boggy conditions - and are nitrogen fixers.
Serviceberry, Prunus sp., and bigleaf maple might do ok, too!

-cc

sounds a bit like what we dealt with here..we dug out the really low wet area and made a pond..see my blog..the fill from the pond will give you some raised areas around it..that are quite dryish..great for growing some more fruit trees and helps the frost to drain away as well as the water

I'd dig soil pits to look at evidence of the effects of soil moisture (google redoximorphic features)... you might get a better idea of duration and consistency of inundation. Consider digging some pits so you can track depth to moisture through spring. A heavy soil can through capillary action create low oxygen conditions a foot or more above the actual water table. I have a silt loam that gets saturated in a heavy rain, but slowly drains through 'interflow' when heavy rains stops. Both cottonwood and willow have recently been identified as nitrogen fixers to complement alder as a nurse crops, and unlike alder they coppice, but also unlike alder produce a inferior fuel wood. Tradition in your parts involves drainage, but that just screws up the streams and reduces water storage for the dry summers. The timing of low oxygen conditions can be critical... lots of deciduous trees and shrubs can tolerate the low oxygen as long as they are actually dormant and not trying to sprout leaves.

A classic crop for that situation is blueberry. I have read that pear is more tolerant of 'heavy soil' but no experience. The Bullock Brothers over on Orcas have cleft graft apple to native crabapple. Other such frankenstien activities might be viable... talk to the Bullocks and maybe Mike Dolan at Burnt Ridge Nursery down my way... he has experimented with funky grafting. Subtle differences in topography can become more important as you get closer and closer to wetland... so observe carefully. Oregon ash is a good fuel wood and might coppice well, but I haven't seen proof. Shrubs and forbs will take up a smaller niche and so can fit in wetter and drier microsites.

I ramble...

I think the best start is to see if you like what you can do with the land as it is before a big drainage or eartmoving project. I would look at Serviceberry, Sea Buckthorn, Swamp white oak, and some comfrey as low mulch. Red alder and Ash should do well too. As things get half out of the standing water, try plums and pears on Beta- rootstock -- The native crabapple should be good too, but I haven't tried that...

Comfrey is also good around apple trees, and won't mind when things get wet and soggy...

Paul Cereghino wrote:I ramble...

Please ramble more... some of us are dutifully taking notes.

I live in SW Oregon and have a low area with a seasonal crk. & clay. What naturally grows there are Maples, hazelnuts, & huckleberries.

Matt Smith wrote:Found this:

http://www.extension.umn.edu/yardandgarden/ygbriefs/h-claytrees.html

and this:

http://www.douggreensgarden.com/best-trees-and-shrubs-for-clay.html

Thanks Matt! Those are great lists. I'm excited by Black Locust and Honey Locust, and also really excited to see that Linden trees are on there.

@Chris: yes, all three; salmonberries and thimbleberries were planted all around some years ago, and thrive. Devil's club grows in the woods uphill from us, in a forest dominated by bigleaf.

@Paul: a lot of good suggestions there, thanks! I always love learning new words like redoximorphic.
There are a couple of oregon ash trees planted nearby; the only ones I've seen in this bioregion so far. They seem to be doing well, and are probably getting to coppiceable age.
Alders are growing in profusion nearby, and I'll probably be gathering a lot of their leaves and fallen wood for mulch.
Willows are planted down below along a ditch that drains to a wetland, and there's some old cottonwoods futher away, by the river.
I've been wondering about making a pond in the locations where I see standing water for much of the winter & spring, and the possible impacts it might have. Wondering about the difference between doing a pond-liner approach vs a Sepp Holzer sort of approach, and also wondering if it might create further problems with drainage, mosquitos, etc. Though I love the idea of the warm microclimate and extra diversity of plants it would encourage.

I'm intending to go visit the Bullock's homestead soon. A friend of mine took me on a little tour of the forest garden at the college in bellingham, and showed me some grafts he'd done on hawthorns. That's an intriguing concept to me, since hawthorns seem to be pretty damn hardy.

I've just transplanted a few blueberries around, and mulched 'em with sawdust. Do you know if there's any plants that go well with blueberries? I know strawberries can also thrive with the sawdust mulch; perhaps they'd be a good ground cover companion?

@Eric:
Regarding comfrey: I'm all for it in every way. Also, the other people who live here view it as a rather invasive weed and I might receive a lot of flac for propogating it. Does anyone have any experience with Russian Comfrey, which I've heard is less 'invasive' and has a greater capacity as a dynamic accumulator? Is it true that when grown in the shade of a tree it's less likely to spread? Personally I'd be happy to have it spread itself around but I also have to work with community process…

Serviceberry and Sea Buckthorn are two shrubs I've had my eye on for a while. I'll definitely try them. Is swamp white oak a good acorn crop as well, or is it mostly used for timber & mulch?

Hazelnuts and huckleberries… some of my favorite denizens of the woods nearby. I'll certainly plant some more!

Thank you all for your comments and suggestions!

Much of my hugelkultur is going into similar conditions to yours, and our climate is similar. Mine is brand new so no results yet. In a couple years we should compare results.

agreed!

I'll explain my own situation, which may be of help.

We are in Devon in England, and have similar wet soil - not with the run-off, but the heavy clay in an area that gets a lot of rainfall means that the ground is pretty wet with water standing on the surface over the winter.

About 12 years ago, the previous owners planted about 3/4 of the land with mixed broadleafs. In the local area, this sort of land seems to be generally considered pretty much useless, maybe useful only for grazing. At the time, there were Government grants payable to farmers who converted this sort of land to woodland. The idea being that the grant compensated the farmers for loss of earnings from the land, and of course if the land wasn't earning anything, then it made sense to plant trees and get some money for it.

So, we've got a lot of alders, and a mixture of willow, oak, beech, birch, poplar, ash, and plenty of elder, hazel, crab apple, guelder rose etc. which are generally all doing well, and the wooded areas are noticeably firmer underfoot than the open area.

We are planning a forest garden in the remaining area that wasn't originally planted (about an acre) and are planning a combination of the techniques suggested here. It's pretty flat, but there's a very slight slope, so we'll be digging ditches to lead down to lower ground, where we'll put in a pond. We'll also have 2 or 3 smaller ponds within the forest garden area, and as mentioned before, the excavated earth will build up some areas. We'll surround the area with willow and alder, put in hugel beds, and plant lots of deep-rooted plants to break up the clay soil and add organic matter to improve drainage - we're going to plant lupins and daikon radish first and see how they fare. We are also planning to graft cultivated apple stock onto the existing crabby/crappy apples, which are doing really well, and seem to produce a decent amount of (not very edible) fruit, but looking at how the tress have grown on the site since they were planted, I'm not worried about the wet soil being too much of a problem, especially with the measures we are going to take.

Overall, I'd say that as we have no running water onsite, we are seeing the water as a gift and a real asset, that we just need to manage correctly. Some people have suggested that we should just accept that the area is boggy and plant boggy plants, but I am not prepared to accept that, and am absolutely confident we can improve the drainage and manage this land into a very productive forest garden.

I now find myself asking "what would Sepp do?" quite a lot, and when I look at what he's done - things which people would have said were impossible given the climate, altitude etc - I know that I can definitely grow some fruit and veg in Devon.

Iain Bagnall wrote:Overall, I'd say that as we have no running water onsite, we are seeing the water as a gift and a real asset, that we just need to manage correctly. Some people have suggested that we should just accept that the area is boggy and plant boggy plants, but I am not prepared to accept that, and am absolutely confident we can improve the drainage and manage this land into a very productive forest garden.

In doing some readings at my adopted hometown's local library, I found record of one of the first settlers to my area moving back to where he came from after complaining that he found it impossible "to find a dry spot large enough to set a hen."

I think about that all the time when I'm working, and smile.

Many water loving plants are edible and useful and should possibly not be despised. The Edible Pond and Bog Garden http://www.pfaf.org/user/cmspage.aspx?pageid=79

Thanks Tyler, I'll have a look at that link.
I've been reading Plants For A Future, and some water-loving plants are amazing, so our intention is to have water/bog gardens; we just want to encourage them to move along a little!

Harper Stone wrote:

Regarding comfrey: I'm all for it in every way. Also, the other people who live here view it as a rather invasive weed and I might receive a lot of flac for propogating it. Does anyone have any experience with Russian Comfrey, which I've heard is less 'invasive' and has a greater capacity as a dynamic accumulator? Is it true that when grown in the shade of a tree it's less likely to spread? Personally I'd be happy to have it spread itself around but I also have to work with community process…

Serviceberry and Sea Buckthorn are two shrubs I've had my eye on for a while. I'll definitely try them. Is swamp white oak a good acorn crop as well, or is it mostly used for timber & mulch?

I use the Bocking 14 comfrey -- the seed-sterile cultivars are definitely the way to go! Since you can propagate them very quickly, 5 plants in year 1 can be 50-100 plants in year 2! They will still spread 4" a year or so.
Swamp white oak is one of the best acorns and can handle some extended flooding. It seems like most all oaks do fine in clay..

Don't forget blue elderberry in the shrub layer too! great 'disposable" trees for food and mulch - and grows great with stinging nettle.

Eric Thompson wrote:Swamp white oak is one of the best acorn

Considering putting in some of these... can you elaborate on the acorns? I haven't heard much about them, specifically.

Plants For a Future is indeed a great resource. I've been loving the bog garden section of the book. The problem on my site is that in the late summer (August & September), the whole place is dry, so most marshland plants probably couldn't take it unless i dug out a pond, and even that might dry out then.

Thanks all for the continued inputs!

Matt Smith wrote:

Eric Thompson wrote:Swamp white oak is one of the best acorn

Considering putting in some of these... can you elaborate on the acorns? I haven't heard much about them, specifically.

These are not the biggest of acorns, but are pretty nice size and low in tannins that make them better for human consumption without a lot of processing..

Harper, I wouldn't underestimate a clayish soil in keeping moist 1+ feet down after a winter soak -- anything with decent roots should be more than fine: oak, ash, and most any tree or bush should make it after year 1. comfrey, mint...