Amenity Turf Category H 
This has a minimum height setting of a mower of 100mm and no maximum recommended height of vegetative growth. This category of turf will typically be cut just once or twice a year. It can be suitable for rural roadside verges or for turf being managed for conservation value. It will be cut with either a rotary mower, flail mower or reciprocating knife mower and clippings may either be collected up, for example for use as hay, or similar, or let fly and returned to the surface.
Amenity Turf Category J
This has a minimum height setting of a mower of 150mm and a maximum recommended height of vegetative growth of 200mm. Occasionally the grass will also be cut shorter for silage. This category of turf will typically be cut every 2 to 4 weeks, with a slight increase in frequency to every ten-days during peak growth periods. It is used for turf areas within airfields so as to minimize hazards to aircraft from birds. It will be cut with either a rotary mower, flail mower, reciprocating knife mower or even a forage harvester and clippings may either be collected (especially if any vertical take-off
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TEST 56