The effect of duration of vegetation management on broadleaved woodland creation by direct seeding

Abstract

The need for vegetation management when practising direct seeding, and the potential for using the technique to establish a range of tree and shrub species used for new native woodland creation, was investigated on a good quality, fertile ex-agricultural site in lowland Britain. After 4 years, an average of nearly 20 000 stems ha−1 of all species had established, amounting to 20 per cent of viable seed sown, with the trees from the fastest growing species being over 2.6 m in height on average, with the tallest trees reaching over 3.7 m. Weeding using selective herbicides improved survival by up to 50 per cent and growth rates by up to 80 per cent. Weeding for 1 year gave a significant benefit to overall survival, but weeding for a maximum of 3 years gave the most improvement to survival and growth of the remaining trees. Tree form was improved by increased stocking densities. Direct seeding proved to be a viable technique for creating a mixed woodland of ash (<it>Fraxinus excelsior</it> L.), cherry (<it>Prunus avium</it> L), field maple (<it>Acer campestre</it> L), oak (<it>Quercus robur</it> L.), hawthorn (<it>Crataegus monogyna</it> Jacq.), hazel (<it>Corylus avellana</it> L.), dogwood (<it>Cornus sanguinea</it> L.), blackthorn (<it>Prunus spinosa</it> L.), guelder rose (<it>Viburnum opulus</it> L.), spindle (<it>Euonymus europaeus</it> L.), wayfaring tree (<it>Viburnum lantana</it> L.), sweet chestnut (<it>Castanea sativa</it> Mill.) and sycamore (<it>Acer pseudoplatanus</it> L.). The work confirmed the importance of achieving good weed control immediately before sowing and for at least the first growing season thereafter, to reduce seedling mortality and increase the chances of achieving successful woodland creation by direct seeding.