08 Dec 2011
Lawn Pest & Disease Control

Do I Really Want Fungi in My Yard?

Many consider “fungi” the distasteful evidence that last week’s leftovers are no longer safe to eat. The impressive work of this “green mold or white fuzz,” however, often goes unappreciated. Yet “breaking down and decomposing sugars, starches, cellulose and lignin” is the primary goal of fungi.

As AgriEnergies resources explains, “Biological relatives of these food fungi are commonly found in soil, and they live and grow in a very similar way. These soil fungi thrive in the aerobic portion of the soil and are superb decomposers and nutrient cyclers. Fortunately, beneficial soil fungi are common and widespread in biologically active soils.” (Ground work – AgriEnergy Resources).

Ideally, our soil will be dominated by fungi, but we need to promote the necessary environment.

“Fungi can’t make their own food like plants do. They are dependent on organic substances for carbon. As fungi break down organic matter and residues (dead plant material), fungi recycle important nutrients that would otherwise remain locked up in dead plants and animals. These nutrients then become available in the soil and are used by microbes and plants” (Ground work – AgriEnergy Resources).

Fungi even take on the challenge of decomposing and digesting complex organic material, such as thatch. Using the soil’s nitrogen, fungi turn low nitrogen “woody, carbon-rich residues” into acces- sible sources for other organisms.

Here are some of the benefits of having fungi in your yard and garden:

• Decompose complex carbon compounds (e.g., crop residues)
• Improve accumulation of organic matter
• Break down hard-to-digest cellulose and lignin
• Retain nutrients in the soil
• Extension of plant roots (increase surface area for water and nutrient absorption)
• Solubilize phosphorus in the soil and make it available to plants and other microbes
• Improve soil tilth (help soil particles cling together)
• Help control pathogens
• Break down some chemical residues (bioremediation)
• Impacts soil pH

Bottom line, beneficial soil fungi are workhorses and you want high numbers of them in your soil.
According to the Jeff Lowenfels and Wayne Lewis, authors of the book “Teaming with Microbes,” “Fungi, like bacteria, play crucial roles in the soil food web. Ultimately, from the plant’s perspective anyhow, the role of the soil food web is to cycle down nutrients until they become temporarily immobilized in the bodies of bacteria and fungi and then mineralized. The most important of these nutrients is nitrogen — the basic building block of amino acids and, therefore, life. The biomass of fungi and bacteria (the total amount of each in the soil) determines, for the most part, the amount of nitrogen that is readily available for the plant to use.” (Lowenfels)

It’s especially important that they (fungi) are out there and active during autumn. Soil with plenty of fungi will break down your residues and put those nutrients back in the soil, making them available for next year’s growing season. For example, compost tea applications during the early spring and summer applications are packed with a blend formulated to supply the greatest diversity of bacteria, fungi, in addition to other forms of biology that help support the growth of microbial life. Adding additional microbial products in early fall further helps break down dead plant material (thatch) and ensures you have high numbers of beneficial fungi functioning in your soil.

The basic premise behind the soil food web and the simple answer to why fungi is important is that, when one element in the soil food web gets out of balance, either from chemical treatments or other means, the entire system visibly suffers. Conversely, when the soil food web is in balance, it creates good soil structure, produces nutrients and controls diseases, all key elements in a healthy looking lawn and/or garden and the foundation to the guiding principles of Backyard Organics.

More to come on the soil food web in future articles, so please stay tuned.

01 Dec 2011

Creating a Self Sustained Lawn Care Program and Why Bacteria Play a Large Role

What They Are and A Few Interesting Facts

Bacteria are minuscule, one-celled organisms that can only be seen with a powerful light (1000X) or electron microscope (we’re talking TINY). They can be so numerous that a pinch of soil can contain millions of organisms. Bacteria are tough—they occur everywhere on earth and have even been found over a mile down into the core of the earth.

Bacteria can be classified into five functional groups. Autotrophic (literally, self-feeding) bacteria are photosynthetic. They are the primary producers. Decomposers consume soil organic matter, plant litter, and simple carbon compounds, releasing the nutrients in these substances for use by living plants. Mutualists, such as nitrogen-fixing bacteria, form associations with plants and help them absorb nutrients. Pathogens are the bad guys— they cause disease in plants. The last group, the chemolithotrophs (literally, chemical and rock-eating) obtain energy from minerals rather than from carbon compounds.

Bacteria are common throughout the soil, but tend to be most abundant in or adjacent to plant roots, an important food source.

Actinomycetes are a broad group of bacteria that form thread-like filaments in the soil. They are responsible for the distinctive scent of freshly exposed, moist soil.

Why They Are Important

Bacteria are important in the carbon cycle. They contribute carbon to the system by fixation (photosynthesis) and decomposition. Bacteria are important decomposers in grassland environments. Actinomycetes are particularly effective at breaking down tough substances like cellulose (which makes up the cell walls of plants) and chitin (which makes up the cell walls of fungi) even under harsh conditions, such as high soil pH. Some management activities, particularly those that change nutrient levels in the soil, can shift the dominance of decomposers from bacterial to fungal. When one group becomes dominant where it shouldn’t be, there is also a shift in the rest of the system. The shift from bacterial to fungal dominance, for instance, can enhance the conditions favoring weed invasions on rangelands.

Bacteria are particularly important in nitrogen cycling. Free-living bacteria fix atmospheric nitrogen, adding it to the soil nitrogen pool. Other nitrogen-fixing bacteria form associations with the roots of leguminous plants such as lupine, clover, alfalfa, and milkvetches. Actinomycetes form associations with some non-leguminous plants (important species are bitterbrush, mountain mahogany, cliffrose, and ceanothus) and fix nitrogen, which is then available to both the host and other plants in the near vicinity. Some soil nitrogen is unusable by plants until bacteria convert it to forms that can be easily assimilated.

Some bacteria exude a sticky substance that helps bind soil particles into small aggregates. So despite their small size, they help improve water infiltration, water- holding capacity, soil stability, and aeration.

Wait! Aren’t there also “bad” bacteria? Yes, there are, but some soil bacteria suppress root-disease in plants by competing with pathenogenic organisms. The key is in maintaining a healthy system so that the good guys can do their work.

Bacteria are becoming increasingly important in bioremediation, meaning that we (people) can use bacteria to help us clean up our messes. Bacteria are capable of filtering and degrading a large variety of human-made pollutants in the soil and groundwater so that they are no longer toxic. The list of materials they can detoxify includes herbicides, heavy metals, and petroleum products.

The process that Backyard Organics uses to cleanse and enrich the soil, focuses on the quality, quantity and diversity of the microbiology that goes into our applications.  Diversity is important because, (depending on your soil conditions) every soil is different.  Having a wide variety of bacteria handles a wide variety of deficiencies.  In order for the bi-products of the microbiology to be of any value, however, the soil food web needs to continue its cycle with the help of arthropods, nematodes and protozoa’s, (the shredders, predators and grazers found in the third trophic level of the soil food web).  Backyard Organics provides the necessary predators by using good quality compost, naturally rich with nematodes and protozoa, and then extracts them using our brew process.  We then add a variety of appropriate nutrients that help the microbiology live and prosper until your soil is able to sustain itself.

 

Learn More!

“BLM NSTC Soil Biological Communities – Learn More.” BLM – The Bureau of Land Management. Web. 29 Nov. 2011. <http://www.blm.gov/nstc/soil/learn/index.html>.

Ingham, Elaine. 1998. The soil biology primer, soil bacteria. USDA, Natural Resources Conservation Service, Soil Quality Institute.

Kennedy, A.C. and R.I Papendick. 1995. Microbial characteristics of soil quality. Journal of Soil and Water Conservation 50 (3) 243-248.

Vollmer, A.T., A. Au, and S.A. Bamberg. 1977. Observations on the distribution of microorganisms in desert soil.Great Basin Naturalist 37 (1) 81-86.