Greenkeepers plant and maintain the grass and turf used for parks, gardens and sporting fields. They sow grass seeds and lay turf, mow and trim the grass and prune other plants, water and roll turfed areas and fertilise soil and plants. They may also undertake maintenance on various structures including fences and paths, trim hedges and keep grounds tidy and free from leaves and weeds. They operate and maintain irrigation systems, and other machinery such as mowers. They mark out and prepare sporting areas such as tracks, pitches, greens, courses and fields. Greenkeepers may also undertake some administrative tasks.