FREQUENTLY ASKED QUESTIONS

Topsoil can be improved to meet the excellent topsoil specified criteria. It can be done as long as the availability of material and economic feasibility permitted.

Please go through this FAQ to get the answer

Excellent Topsoil Specification 

General - Topsoil shall be free of roots, clods, stones larger than 1-inch in the greatest dimension, pockets of coarse sand, noxious weeds, sticks, lumber, brush and other litter. It shall not be infested with nematodes or other undesirable disease-causing organisms such as insects and plant pathogens.

Topsoil shall be friable and have sufficient structure in order to give good tilth and aeration to the soil.

Gradation limits - soil shall be a sandy loam, loam, or clay loam. The definition of soil texture shall be the USDA classification scheme. Gravel over 2 millimeters in diameter shall be less than 20% by weight.

Solution:

Top soil can be graded by raking and any mechanical means to achieve the desired standard.

Permeability Rate - Hydraulic conductivity rate shall be not less than one inch per hour nor more than 10 inches per hour when tested in accordance with the USDA Handbook Number 60 method 34b or other approved methods.

Solution:

Permeability Rate can be improved in several ways, and the target of all following treatment is to lower soil bulk density, please refer to this paper.

If the permeability rate is too high, such as sandy soil:

1. Top dress organic compost to build better topsoil on the top layer of the sandy soil.
2. Mix in organic compost into the soil to build a better aerated topsoil (lower bulk density) and better water holding capacity (more capillary channel).
3. Mix in some clay soil together with organic compost to add more water holding capacity and soil adhesivity to form sand-clay aggregate.
4. Mixed in some synthetic water absorbent polymer (Novelgro HIDROGEL) to increase water holding capacity.
5. Promote growth of beneficial soil microbe to produce more soil glue in the long run.
6. Apply Novelgro TERRA to reduce the soil Growth Limiting Factors.

If the permeability rate is too low, it means the soil particle is too small and clogging the water passage and the air passage. So water and air cannot moves freely in and out of the soil. Such waterlogged soil situation will create an anaerobic environment in the soil, which will suffocate plants roots, beneficial soil microbe and has worse soil biology. The conversion process of decomposing organic matter into stable organic matter also being unaerobic, which will yield noxious gas which is poisonous for the environment. Soil this kind of soil definitely need to be improved.

To improve soil with low permeability rate, there are serveral way to consider:

1. Blend in organic compost to open up more air and water porosity to the soil.
2. Mixed in some sand to lossen and reduce the adhesivity of the soil.
3. Mixed in gypsum and Novelgro SOIL GLUE, a synthetic soil particle binder polymer to form bigger soil aggregate in order to has more air and water porosity. The bigger aggregate also reduce erosion, abrasion, and increase soil water holding capacity as well.
4. If needed, build vertical soil auger hole to bring in air passage to the deeper soil level. The vertical aurger hole also act as water and fertilizer solution passage to the plant roots.
5. Apply Novelgro TERRA to reduce the soil Growth Limiting Factors.

Both types of soil need to apply Ecological Farming Strategy by building soil health program (watch the educational video). Please refer to USDA NCRS website

Fertility - The range of the essential elemental concentration in soil shall be as follows:

Ammonium Bicarbonate/DTPA Extraction

        parts per million (mg/kilogram)

                     dry weight basis 

Solution:

Nutrition in soil dan be managed by organic or inorganic fertilizer application. But in often cases, the nutrition in the soil is adequate, but cannot be utilized by plants due to being tied up by many factors exist in soil. And to solve the problem, we need Novelgro TERRA to release the nutrient by its chelating power, and make the nutrition available to plants. for further understanding, please watch our demontration video titled TERRA & TEA.

In this video, the tea leaves in the tea bag resembling the organic matter / soil that tie up its nutrient. So eventough the nutrient content in the small tea bag is actually quite high, but it is not soluble in the surrounding water to be available for plants consumption. Therefore we need Novelgro TERRA to release the nutrient, and make it soluble and available to plants roots.

Acidity - The soil pH range measured in the saturation extract (Method 21a, USDA Handbook Number 60) shall be 6.0 - 7.9.

Solution:

Soil acidity can be managed as the following:

• If the pH is too low (acidic), pH can be increase Liming. Or apply Novelgro TERRA to reduce the acidic soil effect such as metals toxicity.
• If pH is too high (alkalic), pH can be reduced by applying elemental sulfur.

Salinity - The salinity range measured in the saturation extract (Method 3a, USDA Handbook Number 60) shall be 0.5 - 2.5 dS/m.

Solution:

Soil salinity can be reduced by leaching. Whether by irrigation or rain. But in order to achieve that, soil permeability rate has to be in proper range. That is why the clayish soil tend to has high salinity from native salt or fertilizer residual salt.

Chloride - The maximum concentration of soluble chloride in the saturation extract (Method 3a, USDA Handbook Number 60) shall be 150 mg/l (parts per million).

Solution:

Soil salinity can be reduced by leaching. Whether by irrigation or rain. But in order to achieve that, soil permeability rate has to be in proper range. That is why the clayish soil tend to has high salinity from native salt or fertilizer residual salt.

Boron - The maximum concentration of soluble boron in the saturation extract (Method 3a, USDA Handbook Number 60) shall be 1 mg/l (parts per million).

Solution:

Boron toxicity can be reduced by Novelgro TERRA

Sodium Adsorption Ratio (SAR) - The maximum SAR shall be 3 measured per Method 20b, USDA Handbook Number 60.

Solution:

Soil sodium can be reduced by adding gypsum as soil amendment. And the calcium in gypsum will exchange site with the sodium to yield Sodium Sulfate which has low salt index, leachable and inert in high concentration. Gypsum also open up soil porosity which will increase soil permeability rate to improve leaching.

To improve the leaching of Sodium Sulfate from the soil, the soil water permeability rate can be further improved using Novelgro SOIL GLUE. Which will bind soil particles together to form soil particle aggregates. The topsoil will be come more friable and has better tilth, better water and air percolasion.

Aluminum – Available aluminum measured with the Ammonium Bicarbonate/DTPA Extraction shall be less than 3 parts per million.

Solution: 

Aluminium toxicity effect on plants can be controlled by using Novelgro TERRA

Novelgro TERRA will:

• Increase soil pH, reducing soil acidity, thus reducing Aluminium solubility.
• Chelating the aluminium so the aluminium will not be easily soluble by available acids in soil.
• Novelgro TERRA will improve soil Phosphorus availability

Soil Organic Matter Content - Sufficient soil organic matter shall be present to impart good physical soil properties but not be excessive to cause toxicity or cause excessive reduction in the volume of soil due to decomposition of organic matter. The desirable range is 3% to 6%. The carbon:nitrogen ratio should be about 10. A high carbon:nitrogen ratio can indicate the presence of hydrocarbons or non-humified organic matter.

Solution:

Soil organic matter can be increased using several method such as:

1. Applying compost and manure.
2. Growing mixed culture (polyculture) plants, apply no-till land preparation, and encourage minimal chemical weeding method. And recycle back the unharvested plant residue back to into the soil. For it need ecosystem biodiversity and stability to promote balanced soil biology.
3. Apply land sabbath (land rest) program every certain period, and crop rotation.

Refer to educational paper:

1. Paper 1
2. Paper 2

Calcium Carbonate Content - Free calcium carbonate (limestone) shall not be present for acid-loving plants.

Solution: 

Free calcium carbonate can be controlled using elemental sulfur.

The elemental sulfur will combine with free calcium carbonate become gypsum (calcium sulfate), a beneficial ingredient for soil aggregate formation. The elemental sulfur addition will also decrease soil pH.

The quantity of elemental sulfur needed for this purpose can be determined by pH balancing trial soil treatment method.

Heavy Metals - The maximum permissible elemental concentration in the soil shall not exceed the following concentrations:

Ammonium Bicarbonate/DTPA Extraction

        parts per million (mg/kilogram)

                   dry weight basis

If the soil pH is between 6 and 7, the maximum permissible elemental concentration shall be reduced 50%.

If the soil pH is less than 6.0, the maximum permissible elemental concentration shall be reduced 75%.

No more than three metals shall be present at 50% or more of the above values.

Solution:

Heavy Metals toxicity can be controlled using Novelgro TERRA

Phytotoxic constituent, herbicides, hydrocarbons etc. - Germination and growth of monocots and dicots shall not be restricted more than 10% compared to the reference soil.

Total petroleum hydrocarbons shall not exceed 50 mg/kg dry soil measured per the modified EPA Method No. 8015.

Total aromatic volatile organic hydrocarbons (benzene, toluene, xylene and ethylbenzene) shall not exceed 0.5 mg/kg dry soil measured per EPA Methods No. 8020.

Solution:

Phytotoxic constituent, herbicides, hydrocarbons are some of the growth limiting factors remedied by Novelgro TERRA.

It will accelerate the decomposition of the growth limiting factors residue.

Source:

Garn Wallace

Download full copy of USDA Handbook No. 60