Effects of Small Grain Stubble Height and Mulch on No‐Tillage Soybean Production¹

Abstract

Little data are available on the increasing popular practice of no‐tillage planting soybeans (Glycine max L. Merr.) in small grain stubble. To determine the effects of three small grain stubble heights and three straw mulch rates in branching height, plant height, lodging, population, and yield of no‐till planted soybeans, field studies were conducted at Warsaw and Suffolk, Va. for 3 years. Straw mulch treatments were normal amount (✕), twice the normal amount (2✕), and all straw removed (0). The three stubble heights were “Low” (10.2 cm), “Medium” (20.3 cm), and “High” (35.6 cm at Warsaw and 40.6 cm at Suffolk). Neither mulch rate nor stubble height affected final plant stand significantly, but there was a tendency toward fewer plants in the heaviest mulch rate. Mature plants at Warsaw were tallest in the high stubble with no difference between the low and medium stubble; the same trend was shown at Suffolk. Soybean plants grown in the ✕ and 2✕ mulch at Warsaw and the ✕ mulch at Suffolk were taller than those grown in the other mulch treatments. Lodging and pod height followed the same trend as plant height. Seed yield was highest in the medium stubble and ✕ mulch rate. It is concluded that harvesting small grain to leave a 20‐cm stubble produces optimum soybean yields and the addition of mulch shows no benefit.

Cover Crop-Based, Organic Rotational No-Till Corn and Soybean Production Systems in the Mid-Atlantic United States

“…However, cover crop residue can still be pushed into the seed furrow (i.e., hair-pinning), which can impede seed-to-soil contact [31,32]. In such instances, it is common to observe desiccated, non-germinated soybean seed on top of the hair-pinned residue, especially when the soil is dry and the closing wheels are unable to cover the furrow.…”

Management Effects on Harvest Losses and Yield of Double‐Crop Soybean

“…Beaver and Johnson (1) reported a 4% increase in LPH for 0.20 m compared to 0.76-m-row spacing. Increased WSH increased plant height of doublecropped soybean (9,13). Increases in WSH may cause greater soybean stem elongation due to lower insolation near the soil surface and result in higher LPH.…”

Residue management in double‐crop systems: Impact on soybean growth and yield

“…The influence of crop residue on crop height has been mixed; however, most literature suggests that leaving crop residue will either have no impact on crop height or result in an increase (Warren, 2014). Hovermale, Camper, and Alexander (1979) theorized that taller plants could result in increased growth rate response from altered red/far‐red ratios, similar to that found with high soybean planting populations. Nelson, Smoot, Bliefert, and Kittle (2001) further emphasized this concept demonstrating that soybeans were ∼25% taller when planted into 25‐cm stubble as opposed to similar residue loads that had been mowed.…”