Asparagus weeds - Weeds Australia

The composition of native species growing in somehabitats is not always reflected in the soil-borneseed bank. For instance, 74% of plant speciesgrowing on undisturbed secondary dunes along theNSW south coast are not present in the seed bank(French 2010). For example, Banksia species thatstore their seeds in cones have no propagules in thesoil-stored seed bank. Sites that are heavily infestedwith weeds for many years are likely to have aseverely depleted and less diverse native seed bank.Even if seeds are present, some species may requirea fire or other disturbance event for germination tooccur. Understanding the ecology of the vegetationtype you are working in is very important.Before (above) and after (below) A. africanus controlSite resilienceAssessing your site’s resilience will help youunderstand how much natural regeneration islikely to occur. On most sites, resilience will bedetermined by:• The seed bank in the soil.• The amount and quality of surviving remnantvegetation.• Distance from less disturbed sites that can act asnative seed source.• The severity and time span of disturbance(including the severity and length of time of theweed invasion).• The presence of other degrading factors suchas feral animals, erosion and nutrient enrichedstormwater.• The presence of ecosystem elements such asnative animals that disperse seed or help cyclenutrients through digging the soil.Andrew MeiklejohnIndicative guide to site resilience based on age of weedinfestation (adapted from Bitou Bush Management Manual 2008)LOW | resilience | HIGHNewly colonised by weeds; rich native seed bank; broad rangeof native plant species growing; many adult native plantsavailable to flower and seed.Weed infestation for up to five years; strong native seed bank;some native plants growing; some adult plants available forflowering and seeding.Established weed infestation; native seed bank persisting andviable but only apparent over time; few native plants growingand available for flowering and seeding (monitor and assess).Long established weed infestation; denuded seed bank andfew seeding adults (monitor and assess).81