Success, like succession, is a matter of balance.

We know different plants have different needs. Amount of sunlight and water are usually obvious. We might think nutrients would be apparent too. But, as in people, deficiency symptoms show long after the original need, sometimes after it is too late to correct. When we see stress on the plants it is usually a chronic condition only now becoming apparent. Typical response or treatment may be to add a fertilizer to “restore” the appearance of health. If you farm or work with plants you are already familiar with the consequences and trade-offs. You have probably wanted to get at this issue from a different perspective: instead of treating symptoms to look at some of the “root” causes – pun intended.

When we examine the mineral content of a soil, we find, with a few rare exceptions, that all the major nutrients any plant needs are present in the soil. Yet they are not available to our plants. This does not make sense if we look at nature. Natural systems do not require fertilizer and have highly productive plant life. Whether it is a prairie, a forest, or a weed field, plants grow with no “problems.” When we look at human managed systems we see the opposite. Some plants thrive but others do very poorly. (Usually our crops are suffering and the weeds are doing great.) What is different? What is missing or not functioning in the soil that prevents our plants from being healthy? Lack of organic matter? Possibly. Leached-out soils from years of over-tilling and the use of chemical fertilizers? Very likely a contributor. The real answer though, is lack of proper biology.

In a natural soil we find a microscopic world of living organisms: Bacteria, Fungi, Protozoa, Nematodes, earthworms, micro arthropods, and others. These organisms take the mineral content of the soil and essentially make it available to the plants. This nutrient cycling varies based on the conditions of the soil, the plants growing there, and the balance amongst all the different organisms. The idea of plant succession can be directly correlated to this balance of the biology.

In early succession, when we are mainly growing weeds, we tend to see a heavy bacterial population that is growing in a boom to bust cycle, similar to the life strategy of the weeds themselves. Slightly anaerobic conditions in the soil, and high bacterial populations, create conditions that cycle nutrients in an ideal fashion for the weeds. In our pasture systems (a later successional stage) we still see high levels of bacteria, but less anaerobic conditions, more fungi and a more consistent release of nutrients that grasses prefer. When we get into a forest stage, we see the fungi begin to take over, and, again, we see different nutrients being cycled and made available to the plants.

Ecologists still debate what drives succession in natural systems. In human managed systems, the driving factor behind this is often the plant itself. When it wants certain nutrients, it uses its root exudates to attract the biology that can provide those nutrients. The practical implication of this is that we need to have a good diversity of organisms and aerobic conditions. If those organisms are not present in the soil, then the plant does not get the desired nutrients and becomes stressed.

The nutrient cycle, plant succession, biological diversity, and plant health are all interrelated. If any one of these aspects is out of balance then stressed plants result. We can mimic nature by monitoring our systems, and do things to increase the biology. Whether we feed the organisms, add inoculums or just change some practices, we can accomplish a lot of good. Until next time, happy growing.

If there is a beginning, this might be it...

So many things are happening in our world today so quickly that it can be overwhelming.  My purpose is to look at a small corner of our world and try and bring a sense of sanity and usefulness to it.

Our soils are a precious asset that ensure continued life here on earth.  As we continue to progress into the future my hope and goal is to help people understand and preserve what nourishes us.  I believe it is possible to feed the world in an organic and sustainable way without increasing our overall agricultural footprint.  By acting in a thoughtful way, integrating the best of the conventional and organic practices, utilizing the tools at our disposal, chemical and biological, we can produce enough food and preserve our environment.  This may seem a tall order, but it can be very simple, each of us can contribute to a better world.

One of my specialties is the practical understanding of soil biology, how it affects plant and animal health, I will share what I know and I hope that together we can learn more.

The first thought is the title, "Who fertilizes the forest?".  The simple answer is obvious, "nature", but that is not really enough.  The organisms in the soils of a forest are responsible for nutrient cycling, converting organic materials into humus and creating soluble nutrients through predatory cycles.

This is a slight simplification of the idea, but here is a great reference to help clarify this concept.
(http://soils.usda.gov/sqi/concepts/soil_biology/biology.html)

The important thing here is a more practical idea.  We can copy nature.  We can change our perspective from, how to feed plants, to how to feed soil organisms, that will then feed the plants.  Next time I will go into plant succession and how the balance of different soil organisms can influence plant productivity.