Skip to main content

Jason Clark

Assistant Professor & SDSU Extension Soil Fertility Specialist

605-688-4395

Berg Agricultural Hall 310
Agronomy, Horticulture & Plant Science-Box 2207A
University Station
Brookings, SD 57007

Soil fertility guidelines for South Dakota cropping systems

Also by Jason Clark

sunflower field
Mar 02

Crop Hour: Sunflower Webinars

Would you like to learn more about sunflower varieties, pollinators and weed and pest control? Join us Mar. 2, 3, 4 and 5 at 10 a.m. CST.

Three South Dakota fields that claimed prevent plant. The first field is planted with a cover crop. The second field has no cover crops, but tillage was completed to control weeds. The third has no cover crops and weeds are growing throughout.

Prevent Plant: Its Effect on Fall and Spring Fertilizing Plans

Driving around South Dakota, you can see the many acres that farmers were not able to plant. Now that fall soil-sampling season is well on its way, many people have questions regarding how different situations of prevented planting will affect soil sampling and fertilizer application needs.

A group of black heifer calves in a feedlot.

Using Feedlot Manure as a Crop Nutrient Source

Factsheet that reviews the steps to obtain a manure application rate based on crop need, soil and manure testing.