Seed Harvesting for Ecological Restoration: Efficiency of Haymaking and Seed-Stripping on Different Grassland Types in the Eastern Italian Alps

Abstract

Haymaking and seed-stripping are frequently utilized methods of obtaining seeds for use in ecological restoration. We sought to measure the efficiency of these two techniques in different grassland types in terms of the seed mix obtained compared to the seed present in the vegetation. Haymaking and harvesting with a pull-type seed stripper were compared in two different types of eastern Italian Alp meadows: a tall oats (Arrhenatherum elatius) meadow (grass height 70–100 cm) and a low fescue-bentgrass (Festuca nigrescens—Agrostis capillaris) meadow (grass height 35–65 cm). The percentage of seed obtained from haymaking was similar to that obtained from seed-stripping (about 50% of the seed in the standing vegetation). Nevertheless, haymaking efficiency differed less among the two grassland types (with reference to the harvested seeds number per fertile stem, 39% in the tallgrass and 60% in the shortgrass vegetation) compared to the efficiency of seed-stripping (20% and 73%, respectively). With haymaking, the seed mix obtained in both meadows was similar to that present in the standing vegetation before harvesting. With seed-stripping, the similarity was high only in the shortgrass meadow, where the stripping action of the brush affected the whole herbaceous layer, and the downward motion of the brush allowed for effective harvesting. Both techniques were more efficient in the shortgrass meadow than in the tallgrass vegetation.