With many trees and limbs down, I imagine there is going to be lots of wood chips available. So, the following are a few reasons to use wood chip mulch.
With many trees and limbs down, I imagine there is going to be lots of wood chips available. So, the following are a few reasons to use wood chip mulch.
Mulch placed around plants is a good way to conserve soil moisture. Plants that have a layer of mulch over their roots will manage better in drought conditions.
A wood-mulch layer also can help prevent diseases by keeping fruit such as strawberries and tomatoes from touching the fungal infested ground. The same layer will create a barrier, preventing rot-causing fungal spores from splashing onto low growing citrus fruit.
Wood mulches also produce chemical compounds that inhibit the growth of disease causing fungi.
Furthermore, a layer of mulch helps control erosion and reduce weeds. Apply at least 4 inches for good weed control.
When incorporating large quantities of uncomposted wood products, such as sawdust and wood chips, into the soil, it’s a good idea to add a little high-nitrogen fertilizer to prevent a nitrogen deficiency.
This happens because the bacteria need nitrogen as they break down the wood and will take it from the soil. This is only temporary though, because as the bacteria die, they will release the nitrogen. This is especially important for newly planted annuals such as flowers and vegetables.
It should not be a worry with established trees and shrubs since they have a large enough root system to obtain nitrogen from deeper depths.
A healthy soil
Healthy soils are full of life. This life is comprised of literally millions of different species and billions of individual organisms, large and microscopic.
Forty million bacteria can fit on the end of one pin. Other microbes include algae, protozoa, yeasts, fungi and nematodes. Some of these organisms feed on dead organic matter, while others feed on other microorganisms.
As a group, they help recycle nutrients, build the soil structure and most important, help convert organic matter into rich, stable humus.
It is the humus which is the life support system of the soil. Here are six soil problems that can be addressed by adding humus: compacted soils, fluctuating pH levels, infertile soils, sandy soils and clay soils. In addition, a soil rich in humus will help reduce pest insects and disease pathogens in the soil.
The following is a job description of what some of the soil organisms do in building a better soil:
• Bacteria — feed on organic matter, store and cycle nitrogen and decompose pesticides.
• Fungi — some feed on dead organic matter such as crop residues; others are parasites that attack other microbes. Some live in association with plant roots, delivering nutrients to the plant.
• Protozoa — eat bacteria, fungi and algae. The consumption of bacteria slowly releases nitrogen into the soil. Protozoa also convert organic nitrogen, not available to plants, to nitrogen forms that are available.
• Mites — decompose organic matter.
• Nematodes — these microscopic worms eat other worms in the soil and are an important part of the nitrogen cycle. Some nematodes attack plant roots, but most are non-pathogenic.
• Earthworms — expel partially decomposed organic matter which produces nutrient rich casts. In addition, the worms create some small tunnels that aid in the development of good soil structure and water movement in the soil.
Class announcement
I will be teaching a class titled “General Care of Backyard Citrus and Avocado Trees.” The class is slated for 9:30 a.m.-12:30 p.m. Saturday, Oct. 11, on the University of Hawaii at Hilo campus.
This half-day workshop will cover which varieties to plant, preparing the soil, pruning and fertilizing for citrus and avocado trees. Also included is basic information about diseases, insect problems and troubleshooting.
Call 974-7664 to reserve a seat.
Hilo resident Nick Sakovich is a professor emeritus of the University of California. He has worked in the field of agriculture for 30 years. Email your questions to Sakovich at askthegarden guy@earthlink.net. You also can visit his website at www.gardenguyhawaii.com.