Soil Sampling Service
Depth samples can be taken once every five years, or when new ground is being planted. Depth samples are collected from one location in the field below the surface soil at one foot intervals down to three or four foot in depth @ 1-2 feet, 2-3 feet, 3-4 feet.
This soil profile analysis can aid the grower and consultant in understanding the soil chemistry below the plow layer. Plant growth of deep rooted crops or orchards can be influenced greatly by subsurface soil conditions. Changes in texture and hardpans should be noted when taking the sample.
A surface sample is analyzed for all major and minor soil nutrients (NO3-N, PO4-P, Ca, Mg, Na, K, Fe, Mn, Zn, Cu, B, S, EC, pH). A texture analysis may also be performed. Depth samples are tested for major soil nutrients (NO3-N, PO4-P, Ca, Mg, Na, K, pH, EC) and texture analysis.
When a nutrient deficiency or toxicity is suspected, a sample should be taken from the affected area as well as from an adjacent area where healthy plant growth is occurring. Comparing good and bad areas can provide quick answers when problem solving.
Simultaneous collection of a plant sample taken from both areas for nutrient analysis or visual inspection can help clarify the situation.
- Prepare a sampling plan, simple random sampling or a grid layout, prior to entering the field.
- Talk into the field at least 300 feet when taking a depth sample.
- Take samples prior to planting.
- Take samples from the side of the planting bed.
- Don’t take samples from the strip of soil where banded fertilizer has been applied.
- Collect 25-30 subsamples for a surface sample.
- Don’t sample small sections of different soil texture within the field.
- Take all surface subsamples from the same depth.
- Use a soil probe or auger and a clean bucket.
- Don’t contaminate samples with sampling tools, for example, a rusted shovel.
- Transport the sample in a container that will not break or leak if soil is moist, such as a plastic bag.
- Record the previous crop of the field.
- Record the crop to be grown.
- Record the type of irrigation being used.
- Record any recent fertilizer application.
- Keep soils cool when temperatures are high, refrigerate if possible.
- Deliver samples to a laboratory within 24 hours of sampling.