Defoliation of Panicled Tick‐Clover, Tweedy's Tick‐Clover, and Tall Bush‐Clover: I. Winter Survival and Yields of Nitrogen, Herbage, and Seed

Abstract

electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. L egumes can contribute substantial N fi xation to natural and agricultural systems (Brink and Fairbrother, 1988). Few non-native, perennial, warm-season herbaceous legumes, however, have been identifi ed as widely adapted to the southern Great Plains of North America, so the search is on for natives that will fi ll the gap. Of more than 20 genera of herbaceous perennial legumes native to north-central Texas and south-central Oklahoma (Diggs et al., 1999), only a few have been evaluated for cultivation (Muncrief and Heizer, 1985;Schweitzer et al., 1993;Muir et al., 2005). Th is severely constrains the use of herbaceous legumes for cultivated pastures, green manure, rangeland restoration, right-of-way reseeding, native prairie re-establishment, biofuel production, and wildlife plantings.Native tick-clovers (Desmodium spp.) and bush-clovers (Lespedeza spp.) have been documented as important wildlife vegetation in Texas and Oklahoma (Gee et al., 1994;Stevens et al., 2002;Dillard et al., 2006). Data indicate that they are heavily browsed in late summer and autumn by white-tailed deer (Odocoileus virginianus), and nutritive values (Posler et al., 1993;McGraw et al., 2004;Muir et al., 2005) indicate promise for both extensive and intensive applications. However, little is known of their persistence, forage, C, N, or seed yields under defoliation. With interest in C-negative biofuels from lowinput high-diversity native grasslands on the increase (Tilman et al., 2006) and legume N fi xation sought as an alternative to industrial fertilizers (Sprent, 1999), both C and N yields from native legumes are important to today's agricultural and natural systems.Seeds of 23 native, herbaceous perennial legumes were collected from more than18 rangeland sites in Texas and Oklahoma during 2000. Th ese were planted in small plots the following spring and evaluated for establishment, herbaceous production, and seed yield (Muir et al., 2005). Of the 15 that survived, three were selected for further agronomic evaluation based on herbage nutritive value as well as ease of seed harvest. Th is research evaluated herbage dry matter (DM), C, and N yields of those three (Tweedy's tick-clover, panicled tickclover, and tall bush-clover) under three levels of defoliation. Seed number and winter survival were measured to determine persistence and reproductive potential under four levels of defoliation. MATERIALS AND METHODSIn February 2004, seeds of tall bush-clover, panicled tickclover, and Tweedy's tick-clover were scarifi ed, inoculated with a general "cowpea" Rhizobium inoculant (EMD Crop BioScience, Brookfi eld WI), and germinated in 100-mL containers fi lled with topsoil collected at the Stephenville, TX (N 32° 15´, W 98° 12´, altitude 395 m) fi eld plot site. Th e soil in the experiment area was a Windthorst fi ne sandy loam (fi ne, mixed, active, thermic Udic Paleustalf) (pH 6.6, 11...

Defoliation of Panicled Tick‐Clover, Tweedy's Tick‐Clover, and Tall Bush‐Clover: II. Herbage Nutritive Value and Condensed Tannin Concentrations

“…Tweedy's tick‐clover was consistently higher in NDF concentration than the other two entries, 35% higher in the case of the 40‐cm harvest (Table 1). This may be related to Tweedy's earlier flowering compared to the other two entries (Muir et al, 2008a). Tall bush‐clover had lower NDF concentration than panicled tick‐clover only in the establishment year (2004), a reflection of its immature growth compared to the tick‐clovers the first year.…”

“…The soil in the experiment area was a Windthorst fine sandy loam (fine, mixed, active, thermic Udic Paleustalf) (pH 6.6, 11 mg P kg −1 , 196 mg K kg −1 , 902 mg Ca kg −1 , and 168 mg Mg kg −1 using the TAMU‐EDTA extractant method, Hons et al, 1990). Establishment, management, experiment layout, treatments applied, and climatic conditions are described in Muir et al (2008a)…”

Sustainable, low‐input, warm‐season, grass–legume grassland mixtures: mission (nearly) impossible?

“…), prairie bundleflower ( Desmanthus leptolobus ), leadplant ( Amorpha canescens ), false indigo ( Amorpha fruticosa ) and Rhynchosia latifolia (Posler et al. , 1993; Muir and Bow, 2008; Muir et al. , 2008; Pitman, 2009b).…”

Feeding panicled tick-clover to growing goats reduces Haemonchus contortus infection without negative effects on growth

“…Panicled tick-clover (PTC) is a warm season perennial legume native to much of the warmer regions of North America that flowers late in the growing season, and can grow up to 1.2 m in height (Diggs et al, 1999;Muir & Bow, 2008). Crude protein in this species ranges from 15 to 20%, and contains up to 12% CT on a whole plant basis (McGraw et al, 2004;Muir et al, 2005;Pawelek et al, 2008).…”