Analysis of Soil Fertility to Determine Suitability for Native Riparian and Wetland Restoration

Purpose: Collection and analysis of native soils will be performed within the Clark Fork River Delta Project area to determine nutrient content, organic matter and PH in the upper soil profile (0-12”).   Test results should provide valuable information regarding the suitability of soils at the site for supporting planted and naturally colonizing native vegetation.   The soil test will consist of a standard fertility analysis measuring key soil nutrients for plant growth including nitrogen, phosphorous, and potassium.   Organic matter and PH will also be tested for each sample.  Sampling will be done within discreet subareas of the restoration site using a Stratified Random Sample approach.  Samples will be collected and sent to the University of Idaho Analytical Sciences Laboratory in Moscow, ID for assessment in fall 2013.  Test results may identify nutrient deficiencies or undesirable PH levels or organic content that can limit plant growth.  These deficiencies can be corrected through supplementation prior to initiation of planting or natural colonization of the site.

Sampling Methods: Soil sampling methods will follow those outlined in the University of Idaho Cooperative Extension System Bulletin 704, Soil Sampling.   Soil samples will be collected in spring, 2014.   Composite samples will be obtained from randomly selected locations within discreet sampling areas indicated on the site map below.

Composite samples will be comprised of a minimum of 10 subsamples taken within each area.   However, the number of subsamples will vary across areas and will be dependent on the size of the area being sampled.   The number of samples will be increased with increasing area as described in Table 1  of the University of Idaho Cooperative Extension System Bulletin 704, Soil Sampling.  Samples will be collected within the top 12 inches of the soil profile using a soil probe.   Subsamples will be mixed thoroughly in a plastic bucket and the composite sample placed in a clean and clearly labeled plastic bag.

Timeline – The timeline for this monitoring effort is as follows:

1. Collection of soil samples – Winter 2013/2014
2. Shipment of samples to U of I Laboratory – Spring 2014
3. Submission of Lab Results and Preliminary Assessment Report – June 2014
4. Submission of Summary Report – July 2014

Results