October 8, 2021

Forest Garden: Poking Around in the Dirt

While Dan has been working on the outdoor kitchen cookstove, I've been working on the forest garden (you can see photos and read my planning post, here). As with all gardening projects, the first step was to grab a shovel and take a good look at the soil.

The area of the forest garden is located at a high point on our property (see link above). It is roughly triangle shaped. Contour-wise, I'm looking at this:

High and low spots in the future forest garden.

In the above photo, the yellow line represents a small, shallow ridge. This is the highest spot. The blue oval is the lowest spot, which is dish shaped. In walking the area and looking closely at the ground, I observed several things.

The ground along the ridge - no topsoil.

Trees and brush have grown here for many years. After we fenced in the pasture, the goats ate the brush, which opened up the area. Dan took out a few trees, but most of them have remained and will form our forest garden canopy layer. That means a lot of leaves are dumped on the ground every fall, yet, the top soil is pretty much washed away. 

A little farther down on the ridge the soil seemed softer, with a few bricks lying around. I started poking around with a shovel.

Sand and buried bricks.

Under the thin veneer of decayed leaves, I discovered pure sand and buried bricks. The sand looked like builders sand, and it seems this spot was a dumping ground long ago for leftover materials from a building project.

Also found, homestead relics?

Neither absence of topsoil nor sand hold water, so I'm going to have to do a lot of work on the soil here if my forest garden is going to thrive.

In the low spot, the surface soil looked much, much better:

The ground in the blue oval in the first photo - lovely black topsoil.

When I dug here, I discovered the soil looks like this:

Thick black topsoil and clay subsoil.

The topsoil is black (indicating a lot of decayed organic matter), sandy (which is typical of our cecil sandy loam topsoil), and about five to six inches deep. That was a pleasant surprise because in most places around the homestead, black topsoil (if there is any) is less than an inch deep.

What to make of this? My theory is that most of the fallen autumn leaves are washed off the little ridge in heavy rains and deposited in the low spot. That would explain the absence of topsoil on the ridge and the thick layer of black topsoil in the low area.

I found another relic while digging in the soil here.

It was buried about 6 or 7 inches down.

The other observation that is noteworthy, is that even after several inches of rain in previous days, the soil was only moist in the top three inches or so. Beneath that, it was bone dry. That surprised me too and indicates that the ground isn't getting a deep soaking, even with a lot of rain. This information tells me that our conditioning the pasture soil with a subsoiler was a good decision. For the forest garden, the subsoiler isn't feasible, so I'll need to work on other ways to deep soak the soil.

So, this is my starting point. Hopefully, over time, I can document positive changes in the soil in my forest garden. For now, I'm pulling out all the soil building strategies I can muster, and getting ready to put them to work. 


Ed said...

My biggest take away from this post is that I need to hire out someone with goats to clean up the understory at the back of my property. They do excellent work!

Leigh said...

Ed, they do indeed! Some people do goat powered brush clearing.Makes for happy goats and happy property owners!

wyomingheart said...

That is a mighty fine starting point, Leigh. Do you think sweet potatoes would grow up on the ridge? I had great success in building soil up in Florida, with sweet potatoes. I wish they would grow here… wishes…lol ! Great pondering post!

Leigh said...

Sweet potatoes is a good idea. Thanks for sharing that about soil building with them! I know Geoff and Bill mention them frequently in the lectures, but then, sweet potatoes are perennial for them. I'll definitely try some there next summer.

Rain said...

I learned so much from reading this post. I have zero top soil (visible anyway) because the previous owners were quad people and they put gravel all over the place for their driving. With the years of leaves falling and covering the ground, I will have to dig deep to find any soil. But we mostly have rock and clay here. Thanks for the visuals, it helped me understand a little bit more!

Toirdhealbheach Beucail said...

Mystery. I like mystery. Your discoveries were very cool (and unexpected).

The information about your soil was also interested - and confirmatory, it seems.

Leigh said...

Rain, you're facing a common problem. What you will have to focus on is making your own soil. That means lots of compost making, and cover cropping for slash mulch. It may take a few years, but you can make the best DIY soil yourself!

Rain said...

Thanks Leigh!

Cederq said...

What kind of plants are destined for your Forest Garden? Are you planning to amend the soil by a rototiller or by double shoveling around the trees? What kind of cover crops would thrive under a shade? Sweet potatoes might do well, but be small. Would penetration aerating work to wet the lower reaches of the soil to jump start the soil building?

Leigh said...

TB, the first step in problem solving is observation and fact gathering! And yes, we do seem to be getting confirmation that we are heading in the right direction. That, in itself, is a big relief.

Leigh said...

Kev, all good questions! Stay tuned for upcoming posts with answers!

daisy g said...

Oooh, an enticing new project! Your "groundwork" will no doubt pay off!

Leigh said...

Daisy, I hope so!