Table of contents

Liming Acid Soils
Lime is applied to acid soils to neutralize excess acidity that causes reduced crop yields. The application of lime does not improve saline or solonetzic soil conditions. There are over 1 million acres of strongly acid and 4.5 million acres of moderately acid soils farmed in Alberta. While many factors, such as the kind of crop, soil type, and climate, influence responses to lime, it can be generally stated that the application of lime should be considered on all strongly acid soils and on many moderately acid soils to improve and maintain productivity. Where liming is an established practice, it is applied to maintain soils in the most suitable pH range for the crops and soils in the area.

Soil pH and Plant Nutrients
Soil pH does play a role in nutrient availability. Should you be concerned on your farm? Be more aware than concerned. Keep the pH factor in mind when planning nutrient management programs. Also, keep historical records of soil pH in your fields. Soils tend to acidify over time, particularly when large applications of NH4+ based fertilizers are used or there is a high proportion of legumes in the rotation. Recent years have shown the pH decline occurring more rapidly in continuously cropped, direct-seeded land. On the other hand, seepage of alkaline salts can raise the pH above the optimum range. So, a soil with an optimum pH today may be too acid or alkaline a decade from now, depending on producer land management.

Wood Ash: An Alternative Liming Material for Agricultural Soils
Many forestry facilities in Alberta use bark, sawdust and yard waste, commonly referred to as "hogfuel," to generate steam, electricity and heat for plant operations. There are also several facilities that use hogfuel as an energy source to generate electricity. More than 180,000 tonnes of energy system wood ash produced annually at pulp mills, sawmills, oriented strand board and fibre board plants is currently disposed of in industrial or regional landfills.