We've had good rains this summer and the grass has been growing like crazy. We decided to do a preliminary cut now in December as it was long enough for baling. Our smallholding was originally planted many years ago with Smuts finger grass (Digitaria eriantha), a very palatable indigenous, tufted grass, which offers good quality summer grazing from middle November. The advantages of Smuts finger are that it is drought tolerant, adaptable to a wide range of climate and soil types, good palatability, is suitable for hay and foggage, has a long life-span and is a strong self-seeder.
The limitations are that it has poor water logging tolerance and does not tolerate bad grazing management.
Seeing as we don't do any "farming" activities as such, it has been left to its own devices. Now it is worrying that my fields seem to be getting overtaken by two specific weeds. One with (beautiful) little yellow flowers (above), which I'm still trying to identify and the other is the (beautiful) Pom-pom weed (Campuloclinium macrocephalum) from the Asteraceae family (below). Also classified as a perennial herb with fluffy pink flower-heads, the stems are green to purplish, up to 1.3m high, dying back annually to a root crown. Leaves are light green, scattered along the length of the stem but clustered at the base to form a rosette, up to 80mm long and 20mm wide, margins are serrated. The flowers are light purple to pink compact flower-heads that are situated terminally and it flowers December-March.
The Pom-pom weed produces fluffy seeds that are wind dispersed and people contribute to spreading the seeds through carrying them in the mud on their vehicle's wheels or by picking and discarding the mature flower-heads and thereby spreading the seeds. It can also regenerate from underground root stalk. I think my weeds appeared when we first had our fields cut by an outside contractor a few years back, probably carrying the weed in on the tractor tyres, because before that the grass showed no sign of weeds.
Pom-pom weed was probably introduced in South Africa as an ornamental plant. The earliest record in the Pretoria National Herbarium is of a specimen collected in Johannesburg in 1962. Currently it is most prominent in Gauteng. The earliest record of its establishment in the wild is from Fountains Valley, Pretoria in the early 1960s and Westville near Durban in 1972. In the 1980's its distribution expanded in the Pretoria area, and it was also recorded from Hilton in KwaZulu-Natal and Wolkberg in Limpopo Province. In the 1990's it spread further to Port St Johns in the Eastern Cape, Rooiberg in Limpopo and Nelspruit in Mpumalanga. From 2000 to 2003 it exploded in Gauteng and in the Free Sate the first record was in Kroonstad. During the same period there was much spread in the Nelspruit, White River and Barberton areas. By 2006 it had spread to the Piet Retief area in south-eastern Mpumalanga and Swaziland.
The environmental and economic impact is that it threatens the survival of grasslands and wetlands throughout South Africa as it can tolerate a wide range of habitats. It transforms the landscape from green to pink in summer.
Eradication of this plant is through Herbicides registered for use on pompom weed and the two physical methods including uprooting and burning of the plant. Seeing as I don't use or tolerate the use of any pesticides on my smallholding and uprooting each and every weed is not gonna happen, I might just have to be satisfied with a pink smallholding in the future!