Seed recovery and germination of reseeded species fed to cattle

Abstract

Cattle have the potential to act as a low cost alternative for seed dissemination of valuable native species. Data collected from this trial was used to compare seed recovery, rate of passage and viability following ingestion and excretion of 7 plant species. Woods rose (Rosa woodsii Lindl.), snowberry (Symphoricarpos albus L.), purple prairie clover (Petalostemom purpureum Vent.), birdsfoot trefoil (Lotus corniculatus L.), western wheatgrass (Pascopyrom smithii Rydb A. Love, formerly known as Agropyron smithii Rydb.), green needlegrass (Nassella viridula Trin.), and yellow coneflower (Ratibida columnifera Nutt.) seed was used in the study. Two steers were fed a seed-free diet consisting of fresh cut vegetative Kentucky bluegrass (Poa pratensis L.)-alfalfa (Medicago sativa L.) forage. Following a 13 day adjustment period to the diet, steers were fed a single dose of a known number of seeds, and total feces collection was conducted for 168 hours post dosing. Fecal sub-samples were subjected to a stacked screen washing procedure for seed recovery and analysis. Seeds from both pre- and post-ingestion were tested for hard seededness, firm ungerminated seed, and germination. Seed recovery varied between seed types, ranging from 5.9% of total ingested seed for western wheatgrass, to 86.3% for Woods rose. Excretion patterns for ingested seed varied between seed types, with 50% of excreted seed being recovered between 30 to 54 hours post-dosing. Seed ingestion and passage through the digestive tract reduced viability. Cattle dissemination of viable seeds (as a % of ingested) such as Woods rose (77.4) and snowberry (69.3), would be a feasible method of delivering large numbers of viable seeds onto selected areas. Dissemination of birdsfoot trefoil (17.5), green needlegrass (11.9), and purple prairie clover (7.2), yellow coneflower (3.8), and western wheatgrass (1.3), using cattle would be less efficient, implementation should be based on seed access and cost.