Management of heather Calluna vulgaris-dominated heathlands in Western Europe is typically undertaken by a combination of techniques including burning, turf-stripping, grazing and cutting. Perpetuation of heather is usually a primary management goal. Vegetative regeneration capacity of Calluna may be age related and nutrient status of the plants might also be important. This Dutch study investigated vegetative Calluna regeneration after cutting in relation to plant age and levels of fertiliser applied, on three heathlands.
In November 1980, 426 Calluna plants, varying in age (1 to 20 years) were cut at 5 cm above the ground on the Oud Reemsterveld (52°5'N, 5°20'E); samples older than 20 years were cut (August 1981) on Dwingeloo heath (52°50'N, 6°20'E).
The effect of fertilizer addition was assessed on Hoorneboeg heath (50°15'N, 5°10'E) the experiment initiated in 1981. In March 1983, 10 Calluna plants were cut at 5 cm above the ground in each of three plots with different fertilizer treatments (0, 200, 400 kg NPK/ha/year; ratio 14:16:18). Regrowth was harvested in August 1983. Total nitrogen content of stems, roots and young sprouts, and carbohydrate reserves in stems were determined.
After cutting, annual rings (indicative of plant age), total number of stems per plant, and number of young sprouts were counted, and dry weight per sprout recorded.
About 90% of Calluna plants up to 6 years old resprouted after cutting. From 7-20 years age, the percentage of regenerating plants decreased steadily and the number of new sprouts produced decreased significantly. However, growth rate of sprouts increased with plant age, being highest in plants of 13 years and older. No sudden regeneration decline occurred in plants older than 15 years (as reported in some other studies) although yield was very low (approx 148 g/m² in 1-3 year-old plants, declining to around 10g/m² in 16-21 year-old plants).
Fertilizer depressed vegetative regeneration. Carbohydrate reserves in young plant stems were significantly larger than in old ones (regenerative capacity positively related to amount of reserves) and reserves in stems of plants in plots with fertiliser added were significantly smaller than in unfertilized ones.
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