At a recent garden party (perhaps that term is a bit too formal for a group of couples hanging out eating pizza while the kids run around like wild animals), part of the conversation covered the host’s lovely vegetable garden.  I’ll admit to some envy at the size and beauty of the tomato plants in the organized suburban garden setting, compared to the young scrappy looking vines out in my rural plot.  During the chat discussion shifted to slug control measures.  It seems that the beer traps work well, but require continued vigilance.  Grapefruit halves and egg shells were mentioned as other effective methods but no one seemed to have direct experience with those techniques.  I left the conversation intrigued and newly aware that we haven’t had any slug issues this year.  That sparked my curiosity.

Don’t get me wrong, I have found an occasional slug in the garden, but nothing that would cause concern.  There are many potential reasons why slugs might not be a pest problem in my garden while our fellow party goers were exploring control methods a few miles away.  Microclimate, garden location, orientation to the sun, soil moisture, shading, nearby structures and soil composition are just a few of the possibilities.  My favorite answer, and most probable one, is predation.  In one of my earlier blog entries I shared a photo of a toad sitting in the newly constructed hugelkultur garden bed.  A few weeks ago my wife spotted a turtle lounging under the shade a few feet from that same garden.  Toads and turtles love to eat slugs.  I suspect these guys are dispatching the slugs before they do much damage or I get the opportunity to view them.  On our property, that toad has several brothers, sisters and cousins living near the small stream, in the natural drainage channels, in the landscape beds and in our multiple vegetable plots.  The more slugs, the more toads can move into the area to eat.  While toads and turtles might not seem like predators from my viewpoint, I suspect they are high on the list of threats to a slug.  But why we don’t have toad infestation problems?  I suspect the slug to toad / turtle population has reached a point of stasis or the raccoons, coyotes and hawks have created a similar balance with the toad as prey.

Natural ecosystems are all about long term balance.  Slug or toad infestations will occur periodically.  One species may rise to infestation level in an area for a period of time.  Any system will have occasional variances, but a well-balanced system will self-modify and self-correct.  Predators often play the critical role in ecosystems.  Population explosions by one species will eventually attract its predators and parasites.  Those predators themselves may grow in population but this should balance as the food source disappears or new predators and parasites emerge to prey upon the new imbalance.

Permaculture is a systems based approach to agriculture.  Plants and animals are selected to play a role within the community toward a goal of symbiosis and balance.  Diversity and polycultures are preferred over monocultures.  The clover used as ground cover attracts pollinators and fixes nitrogen for other plants in system.  Some species are chosen to draw nutrients deep in the soil near the surface where it can be accessed by others.  Helpful insects and wildlife are encouraged to thrive along with useful livestock management.  Even the litter and waste serves an important purpose in the system.  Preference is given to perennial or self-propagating species toward a long term self-sustaining system.

Within the permaculture community, some are experimenting with the transfer of these concepts from the fields and forests into human society.  At first blush that seems a little hippie or libertarian to me (I’m a moderate at heart), but from a systems thinking standpoint I can’t help but be drawn to the concept.  Upon reflection it doesn’t seem that different than the last hundred thousand years of human society, with the notable exception of the last few hundred years.  I also can’t help having misgivings over the impact of human population expansion and impact within our ecosystem.  Natural systems seem to find ways to self-modify and self-correct to reach stasis. 

We humans are an intelligent species.  Perhaps we’re intelligent enough to maintain and sustain an out of balance system.  For some reason I’m doubtful that we’re that intelligent.  I am hopeful that we are smart enough to find ways to create more balance and some sort of stasis so nature doesn’t take things into her own hands.  The likely result ends up with nature treating us like another population infestation, rebalancing population levels through food shortages, predators / parasites or outright extinction.

As for our little forty acre slice of earth, I’m going to try to take as much pleasure in the coyote, hawk and raccoon as I do in the toads, turtles and turkeys.  That won’t be easy.  I suppose we could end up losing some of our chickens or even one of our dwarf goats.  The kids will cry.  I'll be frustrated.  But the coyotes are just being coyotes, playing their role in the ecosystem.  They have moved here to Ohio because we no longer have red wolves.  While the bobcat still lurks in some southern Ohio forests, the only Ohio bobcat most of us will see in a lifetime is the one on a collegiate sweatshirt.  So when I see those predators I'll try to pause, recall those permaculture concepts and try to take solace in the fact that the higher predators are a sign of a healthy and balanced ecosystem.

Last fall I was introduced to the concept of German raised bed gardening known as Hugelkultur when a friend on the west coast installed a few hugel beds.  Not being one to miss an opportunity to explore something innovative, I spent some free hours over the winter researching the concept.  Paul Wheaton’s website has a great overview of hugelkultur at http://www.richsoil.com/hugelkultur/.

Hugelkultur raised beds are constructed by building hills of logs, brush and sticks and covering the hill with soil and compost.  The raised bed can then be planted with your annual or perennial fruits and vegetables, trees and other garden goodies.  The most notable benefit of a hugelkultur bed over a traditional garden plot is the reduced need for irrigation.  The buried wood works much like a sponge, soaking up excess water during periods of heavy rain and releasing water slowly into the bed during dry periods.  The taller the hill, the longer your hugel bed can withstand lack of rain or irrigation.  Some sites indicate that a six foot tall bed can go months or even an entire growing season without rain, supplying all the water necessary for your plants from the stored water in the wood.  The wood will slowly decompose providing an embedded source of humus for your garden.  Other benefits include improved aeration in the bed, improved drainage, heat generation from the composting process (the first few years) and a productive way to make use of those fallen branches and brush littering the property.

Every good idea should be tested and applied, so I spent several weekends in March building a test hugelkultur bed on the farm.  With over 20 acres of forest we have an ample supply of fallen trees and branches.  A few online articles and blogs raised a concern that the wood would rob nitrogen the first few years as the composting process got cranked up.  I can understand the point and decided to dump a few tractor bucket loads of horse manure, from those compost machines in the barn, on top of the wood.  My neighbor has a trucking and excavation business and he dropped off a load of topsoil that went on the top of the manure.  The photo series at the bottom of the post showcases the progress.  These were taken late in the evening after each day's additions so but I don't think the long shadows mask too much detail.

After completing the bed and letting it sit for a few weeks it was time to get planting.  I am a big fan of perennial crops (aka lazy gardener).  Unfortunately, most of our soil is better classified as dirt.  I have tried a few times to establish beds for rhubarb, asparagus, raspberries and strawberries but failed to get a thriving plot established. My first hugel runs east to west so I decided to plant the rhubarb on the south side, asparagus down the top, strawberries as a ground cover, and the raspberries on the north side.  As the canes get some height they should peak over the top of the bed reaching for the sun.  I also had a few pounds of seed potatoes I planted into the east and west ends of the bed.

The dimensions on the hugelkultur bed measure 12 ft. long, 4 ft. wide and 4 ft. tall.  This is quite a tall and steep raised bed.  It takes some adjustment to viewing and planting.  At several points during the process, I questioned whether this would really work, but I had to give it a try.  My plot is out of sight of everything but the wildlife, but I could see why some people may have concerns over appearances in a suburban setting.  You still achieve some of the benefits of the approach on beds as short as two feet tall, which may be a more practical approach for many gardeners.

If this test bed is a success I hope to build several more for next year.  I will post some update photos once the growing season gets into high gear.  In the meantime, I found a toad lounging on the steep banks of that hill this week.  I view that as a very positive sign for a fruitful future.