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The composition of humid, unfertilised, short‐tussock (Festuca‐Rytidosperma‐Poa) grasslands was recorded on 42 permanent transects in 1959, 1970–72, and 1995–96 in the Wairau catchment, Marlborough. Changes in frequency of the most abundant plant species and bare ground were analysed. Reduced levels of grazing, browsing, and fire prompted significant recovery of native shrubs, tall tussocks (Chionochloa), and herbs. Invasive exotics (Hieracium, Anthoxanthum, Agrostis) also increased. Short native grasses (Poa, Elymus), a native herb (Acaena spp.), and an exotic herb (Rumex acetosella) declined. Hieracium pilosella, H. caespitosum, and H. lepidulum were rare or absent in 1959. By 1996 they had established on half the transects, but were still in the early stages of invasion (median frequencies ≤ 5%). There was no correlation between the increase in Hieracium and decline in other species, suggesting that other factors were driving the compositional changes. However, Hieracium species can establish ...

The distribution and density of Hieracium pilosella, H. caespitosum, and H. lepi‐dulum seedlings were quantified at an early stage of invasion of a tall‐tussock (Chionochloa) and a more open short‐tussock (Festuca‐Poa) grassland. Seedling and available (unoccupied) microsites were compared in 11 stands. Recorded variables included establishment substrate, overhanging cover, and proximity and height of neighbouring plants. Total Hieracium cover was