Member Highlight

LP Consulting: Guiding biosolids & residuals use on farms in the Maritimes

September 2014

Lise LeBlanc is an agronomist and the principal at LP Consulting.  (She is also a current NEBRA Board member.)  She and her colleagues recognize the value in organic residuals.  They help farmers choose the right fertilizers and soil amendments to achieve cost-efficient, sustainable fertility on their fields.  They recycle wood ash, biosolids products, gypsum, wood waste, compost, whey products, digestate, fish wastes, and more, using careful analyses for agronomic values and site evaluations to match the soil amendments and fertilizers to the needs of the particular soil and crop.  They are careful to choose products that have been properly treated and tested to ensure safety for the environment.  They are busy throughout Nova Scotia, Prince Edward Island, and occasionally in other provinces.

"We emphasize knowing the agricultural markets where the various residuals are to be used," explained LeBlanc in a presentation to the Compost Council of Canada in September, 2014.  For example, the Halifax N-Viro Soil Amendment product - an advanced lime-treated biosolids - is of great benefit as a liming agent in Nova Scotia, where soils are acidic and the pH must be raised if crops are to be successful.  But the same product may not be so useful in the higher-pH calcareous soils found in parts of western Canada.

Standard commercial fertilizers are important.  But their prices are variable and tend to go up steadily.  They require energy and resources to produce and transport.  And they don't build organic matter in the soil.  "So it's important to access local, renewable nutrient sources for a sustainable future," said LeBlanc.  "Residuals improve soil condition - tilth, aeration, drainage, water holding capacity - and reduce hard pan.  They add organic matter and stimulate microbial activity."

LP Consulting helps farmers understand the value and applications of various residuals.  They conduct soil testing, write nutrient management plans, address regulatory requirements, and help arrange deliveries and applications of residuals. 

On a sunny, late-September day, a group from the annual Canadian Compost Council conference toured a dairy farm north of Halifax.  LeBlanc and the farmer explained the long-term soil fertility management practices that have brought the farm higher crop yields with better nutritional value.  They demonstrated the process of land applying the Halifax N-Viro Soil Amendment biosolids product.

Using residuals is now a routine part of this farm's operations, and the benefits are numerous. The biosolids, which were first applied in 2010, have increased phosphorus to better levels on 86% of the fields and potassium on 69% of the fields.  Meanwhile, soil pH has been elevated to optimum levels for corn and legume forages:  89% of the fields are above 6.0 and 72% are above 6.5.

Halifax N-Viro Soil Amendment is mostly sold by Truro Agromart Group, a standard farm supply and fertilizer dealer.  According to the product label provided by Agromart, it contains the following nutrients:

Total N: 0.8%
Available P2O5: 1.0%
Soluble K2O: 0.5%
Calcium: 10%
Organic Matter: 20%
Neutralizing Value (CaCO3 equiv.): 25%
Moisture (maximum): 38%
Fineness Passing #10 Mesh: 65%
Fineness Passing #100 Mesh: 40%

The responsible fertilizer distributor will take soil samples to determine the rate of application.  Average application rate: 5 tonnes/hectare annually.  N available in year of application: 15 - 20%  Ca available in year of application: 6 - 8%. 

 

Compost Pack Bedding Dairy Barn

The farm tour also showed off another innovative, beneficial practice adopted at this farm: the compost dairy barn system, as described by LP Consulting in a handout provided at the tour....

"Folkerstma Farms Ltd includes 280 dairy cows, 100 heifers and 100 calves.  The farm has a total of 900 acres.  Crops include: corn, legume and grass forage, and pasture.  

"There are several dairy housing systems used in Nova Scotia, with most using Freestall housing.  There has been a growing interest in compost dairy barns, which offers loose housing.  This system has shown good cow comfort and freedom of movement.

"Freestall System: A Freestall system allows the cows to move freely from their resting and eating areas.  The resting areas are comprised of stalls where thy can rest and lie down.  The stalls need to allow room to enter and exit, lie down, and stretch.  Most stalls have cushioning mats but still require bedding to maintain clean and dry conditions.

"Compost Dairy Barn (CDB):  A CDB generally has a center concrete feed alley with a bedding pack on either side of the alley.  The cows can stand on the concrete on either side of the feed alley for feeding and then move onto the bedding pack for rest.  The pack is aerated twice a day to enhance microbial activity and freshen the pack surface.  This is done with a cultivator on the back of a tractor, which incorporates the manure on the surface into the bedding pack material.  A CDB may have lower bacteria counts because of the drying and heating of the composting bedding pack.  Bedding material is added to the pack when it becomes too moist.  The compost pack bedding material is usually removed once per year and applied onto farm fields.

"Compost Pack Nutrient Analysis:
Dry matter (DM): 23.4 kg/tonne
Total N: 3.8 kg/tonne
Ammonium N: 0.4 kg/tonne
P2O5: 3.4 kg/tonne
K2O: 1.95 kg/tonne

"Estimated value (year of application):
Compost Pack:  $5.47/tonne
Liquid dairy manure: $3.88/tonne
Liquid heifer manure: $7.41/tonne