| | Site selection for a nursery will be influenced by several factors. Important considerations include proximity to a market, soil type, pH, slope of the land, climate, water quality, access to irrigation, and availability of labour.
Soil type
The ideal soil type depends on the type of nursery crop grown. A sandy loam soil is desirable for trees harvested bare root, which can be sold as is or containerized for sale. Heavier soils, loam to clay loam, are more suited to trees that are balled and burlapped for sale. Trees do not generally grow well in heavy clay soils due to poor drainage and in very sandy soils due to rapid nutrient leaching.
pH
The optimal pH of the soil for nursery stock ranges from 5.0 to 7.5. In southern Alberta soils are usually at the upper end of this scale or higher. Although some trees will grow at higher pH's, their growth will be suppressed and a poor quality tree is produced. Nurseries should not locate on soils where the pH is 7.5 or higher. A soil test will provide information on pH and available nutrients in the soil.
Slope
Gently sloping land allows for air and surface water drainage, yet still provides for uniform crop development and an efficient operation of equipment and irrigation. Steep slopes are subject to erosion, can produce irregular crops, and limit layout options. Low areas can be cold spots which are prone to frost and may not drain properly during periods of high rainfall.
Environmental conditions
Environmental conditions must be a consideration for site selection. Temperature, light intensity, and rainfall are the major considerations although other factors such as winds and the frequency of hail should also be considered. Rainfall can be supplemented with irrigation and winds can be modified with shelterbelts or wind barriers. Areas with a short average growing season will limit plant material choices and growth will be slow. Trees grow more quickly with high temperatures and light intensity; therefore, reducing production costs. High winds will cause desiccation of the plants throughout the year and should be modified with shelterbelts. Hail can damage the crop and reduce growth; therefore, areas with regular hailstorms should be avoided.
Irrigation
In southern Alberta access to irrigation is necessary while in central and northern Alberta trees are grown in dryland situations. Irrigation water quality should be investigated when selecting a site. Testing the water for electrical conductivity (EC) will determine the salinity of the water. Electrical conductivity, expressed as decisiemens per metre (dS/m), increases with the amount of soluble salts in the solution. Ideally irrigation water should be less than 0.25 dS/m. At 0.25 to 0.75 dS/m, the water is moderately saline and moderate leaching is suggested. At 0.75 to 2.25 dS/m, the water has high salinity and should be used only where good drainage is available, salt tolerant plants are grown, and leaching is frequent. Water with an EC higher than 2.25 dS/m should be avoided.
Labour
In even the smallest nursery operations, additional labour will be required during peak times such as planting and harvesting. Locating the nursery where at least temporary labourers are available becomes an important consideration. |
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