Does spreading calcium cyanamide present a danger for dogs or cats?
There have so far been no adverse effects reported when dogs or cats have access to surfaces freshly fertilized with calcium cyanamide. The calcium cyanamide has a deterrent odor and taste, so that animals naturally avoid ingesting it. The only precaution that should be taken is to keep the animals at a distance while the spreading is ongoing, to avoid them trying to play catch with the flying grains, or getting fertilizer particles in their eyes or mucous membranes.
Does calcium cyanamide help to counteract snails and slugs?
Slugs in particular are relatively sensitive to calcium cyanamide. This is especially true for the slug eggs and the tiny young snails. But there are also a large number of microorganisms that are promoted by calcium cyanamide. Therefore calcium cyanamide can indeed be successfully used in composting as a rotting accelerator. So calcium cyanamide certainly does not leave behind a sterile or "dead" soil. Quite the opposite: long-term tests by the TU Munich-Weihenstephan carried out over many years have shown that the biological activity of the soil after decades of calcium cyanamide use was higher than when other nitrogen fertilizers were used, and exceeded even the biological activity of farmyard manure. Nor are earthworms harmed if calcium cyanamide is used properly: during the short, intense cyanamide phase they migrate into deeper soil layers. This can also be observed in many compost heaps where despite calcium cyanamide being applied regularly to the surface an incredible mass of compost worms can be found harboring deep inside.
Can I still fertilize rape after it begins to emerge?
Well-rooted cultures with non-sensitive foliage (rapeseed, cereals, sunflowers) can even be given up to 300 kg/ha calcium cyanamide as a top dressing of fertilizer. The rapeseed should have developed at least four true leaves. However, the foliage should be dry so that the fertilizer granules do not remain stuck to it but trickle down instead to the soil. If fertilized onto existing stocks then it is vital that the plants are dry, so that no calcium cyanamide sticks to the leaves. The soil, however, should be slightly moist.
Can root weeds (couch grass/wheatgrass, bindweed or goutweed) be combated with calcium cyanamide?
Even using calcium cyanamide these root weeds are very difficult to tackle! Since these plants spread via root suckers, which moreover come up from sometimes great depths, the use of calcium cyanamide is quite limited here. The cyanamide phase of calcium cyanamide acts only in the top 3 to 4 cm of the soil, destroying as a result most of the weeds that have germinated from seeds and even small weeds. Root weeds such as goutweed are hardly impaired at all by this process.
When the cyanamide penetrates deeper into the soil (e.g. as a result of rain) it is converted via urea into ammonium and then acts as a slow-acting fertilizer. One may indeed scorch the leaves heavily with calcium cyanamide when it is spread onto a wet goutweed stock, but experience shows that the plants shoot rapidly back out of the soil.
It is therefore advisable to repeatedly tear out as much of the root parts as possible, so that they cannot store any reserves in their subterranean storage organs. Goutweed, bindweed and couch grass/wheatgrass will then become weaker each time and eventually disappear entirely.
Can ribwort (buckhorn plantain) be tackled using calcium cyanamide?
Calcium cyanamide can be used to continually drive back ribwort in grassland. The best time to apply it is in the spring when vegetation is beginning. Because of its rosette-like leaf arrangement the plantain is at this time, i.e. before elongated growth sets in, particularly sensitive to calcium cyanamide. In particular, when the fertilizer is spread onto the dewy plant stock (contrary to the usual recommendation!), disproportionately large amounts of fertilizer remain sticking on the rosettes, where it leads to severe leaf burn.
The grasses at this point of time do not yet have much active leaf surface, and what they do have is narrow-leaved and standing more upright, so that the burns on grass are kept to a limited amount. The application rate should be approximately 350 kg calcium cyanamide per hectare, corresponding to a dose of 35 grams of calcium cyanamide per square meter.
The fertilization effect that now begins to take hold encourages the growth of the grasses in particular, which then gain the upper hand in the fight against the ribwort plantain. If this procedure is repeated every spring, the ribwort will be suppressed to a tolerable minimum within two to three years.
What are the ideal conditions for applying calcium cyanamide?
Fertilization with calcium cyanamide is usually carried out one to two weeks before sowing or planting, so that by then the cyanamide can be degraded into compounds that plants can tolerate. Intensive soil contact by working in the calcium cyanamide to a shallow depth, a moderately moist soil and warm temperatures accelerate the degradation of cyanamide. At low rates of application (max. 300 kg/ha) and on less sensitive crops such as rapeseed, corn or cereals, calcium cyanamide can be applied even right before sowing.
Well-rooted cultures and non-sensitive foliage (rapeseed, cereals, sunflowers) can even be given up to 300 kg/ha calcium cyanamide as a top dressing of fertilizer. However, the foliage should be dry so that the fertilizer granules do not remain stuck to it but trickle down instead onto the soil. If fertilized onto existing stocks then it is vital that the plants are dry, so that no calcium cyanamide sticks to the leaves. The soil, however, should be slightly moist.
Is calcium cyanamide also effective against buttercup?
Calcium cyanamide has a positive influence on the composition of the plant community: certainbroad leaf weeds are suppressed by using calcium cyanamide because of the way it works, and its long-lasting and even nitrogen effect encourages valuable lower grasses.
It makes sense to fertilize the pasture each year with calcium cyanamide particularly when buttercup is covering large areas of the pasture.
Apart from the direct effects resulting from itsincompatibility, calcium cyanamide also acts indirectly by improving the soil properties:
buttercup likes especially to spread on compacted, moist soil. The intense lime effect of PERLKA improves the soil structure, prevents silting up of the soil surface and promotes the penetration of the water into the soil. This improves the living conditions for the grasses and makes it difficult for the buttercup to spread.
Horse owners have reported a number of times that using this approach they had succeeded in largely repelling buttercup from the area inside 2 to 3 years. Here too, the ideal time to apply calcium cyanamide is when vegetation begins in the spring, and the application rate should be 300 to 400 kg calcium cyanamide per hectare.