Rough hawkbit
Leontodon hispidus s.l. (Schröter, 1888)
BOTANY
Perennial, 10-60 cm high, with a rootstock that is shortly cylindrical, descending aslope or vertically and terminating abruptly.
Single-or multistemmed, with stems erect or ascending aslope or arched, simple, with one flowering head (rarely two) only slightly thickened below and with up to two floral bracts; with hairs or glabrous, capillarily or angularly grooved, mostly longer than the foliage leaves. Foliage leaves basal, forming a rosette, highly polymorphic, oblong to oblanceolate; contracted to a broad indistinct petiole, entire, sinuate-dentate or pinnately split, glabrous or with several forklike hairs (2-3-fid) or stellate hairs. Grass-green to grey-green, with soft to stiff hairs.
Flowering heads are quite large, nodding before flowering.
SUITABILITY FOR RESTORATION
European species that is extremely polymorphic, common and occurs in the Alps, from the foothills to the upper alpine zone. On (alpine) meadows and pastures that are moist to slightly alternating moist and dry, at low-density forest sites, on talus sites and sometimes on rocks.
Multifunctional use for restoration at all altitudes, good forage, filling gaps well. The glabrous subspecies Leontodon hispidus ssp. hastilis grows in the subalpine and alpine zones.
SEEDS
Achene 6-7.5 mm long, 0.7-0.9 mm wide and 0.5-0.7 mm thick; oblong-bacillary, only slightly tapered at both margins, slightly angularly compressed, with fine lateral grooves, highly cross-rugose.
Pappus brownish-white to yellowish, outer hairs are simple bristles, inner ones lanceolate leaflets fading to pinnate hairs, up to 10 mm long (disappearing when cleaned).
Surface auburn to dark brown, slightly glossy.
Thousand seed weight: 1.3-1.5 g.
REQUIREMENTS
(soil and climate)
Rough hawkbit has no special soil requirements. Because of its deep roots it is minimally sensitive to drought. It prefers an intermediate to good nutrient supply. The pH should range between 5.5 and 7.5. Soils that are wet, waterlogged, or tend to a high weed infestation should be avoided, as well as soils that are rich in peat, light, or dry.
Seeds
CULTIVATION
Open sowing is unproblematic, if sowing is carried out by the beginning of July at the latest (at mild locations by the middle of July). In the latter case irrigation of the crop is recommended.
To date no experience has been gained with cover crops.
Seed rate: 10-12 kg/ha are necessary for a satisfactory population density (if the seed quality is good).
Row spacing: 15-25 cm. Depending on the construction of the seeder and the method of weed control there should be either dense populations or sufficient row spacing (for mechanical and/or chemical weed control).
Broadcast sowing is generally possible.
FERTILIZATION
Phosphorus and potassium: on soils with an intermediate phosphorus and potassium content, basic fertilization with solid or liquid manure is sufficient in autumn. If the soil content is on high level, fertilization with 40 kg/ha P2O5 and 60-80 kg/ha K2O is considered sufficient, depending on the yield.
Nitrogen: at the sowing stage, fertilization with about 30 kg/ha of N-total is recommended in order to obtain the best development up to autumn. An application of 60-80 kg/ha of N-total is necessary per year, to be added in autumn, early spring and after the first harvest. If fertilization in spring is carried out too late, the principal outcome will be stimulation of the leaf mass.
MAINTENANCE AND WEED CONTROL
In early autumn before the crop year, cutting makes sense if the populations are densely grown.
If competition with weeds is low, mechanical weed control is sufficient. Rough hawkbit is not sensitive to the use of curry combs. As for all herbs, the control of weed grasses is relatively easy. On the other hand, herbicide control of dicotyledonous weed species is problematical. It is possible to control weeds, mainly in summer and autumn of the seeding year, as well as in spring of the harvesting year, by wiping wick and total herbicides (Glyphosate), and taking advantage of the differences in growth heights.
Pests and diseases: leaf diseases caused by fungal decay are possible, but do not generally lead to losses in crop yields.
At the first harvest, larvae of flies that mine in the flowering heads can cause significant problems. Ongoing control of the flowering heads is recommended. If there is decay, using a systemic insecticide against mining and sucking pests (such as 0.5 l/ha Deltamethrin) is imperative, in order to make the first harvest possible.
HARVEST AND YIELDS
Resistance to lodging: high.
Shattering tendency: high.
Ripeness: after flowering, the flowering heads close and open again after three to five days.
The seeds adhere to the flowering head quite firmly for one or two more days, after which they shed easily, even at a puff. Consequently, the seeds should be threshed, when only 40-50 percent of the flowering heads are open.
Ripening period: first harvest during the first and second decade of June; second harvest between the first decade of August and the beginning of September, depending on the weather.
Harvesting technique: direct threshing is possible. If ripening is unequal, very large sieves, a low rotational speed, and a wide gap between threshing drum and concave are recommended. In this way the withered but still closed flowering heads can also be harvested. After one or two days of cool air ventilation, seeds enter an after-ripening stage, which leads to a belated burst of the flowering heads. As an alternative, harvesting is possible using suction devices whereby the ripe seeds are harvested without destroying the mother plants. Because only completely open flowering heads ensure an efficient harvest, harvesting should take place on warm, sunny days with low air humidity. The first harvest is recommended when about 50 percent of the flowering heads are open. After most of the flowering heads have been harvested, cutting is recommended, in order to stimulate seed formation once again. Altogether up to eight harvests per season can be expected, using this method.
Cleaning the seeds is a simple and easy task.
Flowering plants
Crop yields: because of lack of experience regarding the cultivation of rough hawkbit, yield forecasts are difficult. Yields range between 60 and 180 kg/ha, where the amount of harvests per year are combined.
Optimal maintenance allows up to three harvesting years.
