Weed of the Month – August 2016

KIKUYU

(Pennisetum clandestinum)

   

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OLYMPUS DIGITAL CAMERA

OLYMPUS DIGITAL CAMERA

(Photos: E. Cousins, a patch of kikuyu, one stem, close-up of sheaf and hairs on leaf; Cape Jervis)

Kikuyu is well-known by many as a hardy grass for lawns. This hardy African perennial can withstand the backyard cricket matches, and survive just about any summer. It’ll also spread readily along roadsides or over vacant land with a two-pronged attack: using above-ground creeping stems (called ‘stolons’) and below-ground ones (called ‘rhizomes’). The stolons form a mat with short, folded leaf blades and many joints. Each leaf forms a sheaf around the stem before branching off; leaves can be slightly hairy, and get coarse as they age.  Although essentially prostrate, put a barrier in its way, such as a fence or tree stump, and the kikuyu will climb all over and possibly through it! The stolons and rhizomes are extremely effective at spreading kikuyu (more so than its seed), one reason kikuyu has been labelled an environmental weed in S.A.

Plant of the Month – August 2016

DWARF GREEN-HOOD

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(Pterostylis nana)

(Photos:E. Cousins, flower spike, front and side views)

You often find these in colonies, flowering from July to October, so start watching for them now!   Look for a rosette of leaves at the base. You will find 4-8 thickish leaves, all with smooth edges and short little stems. The leaves are oval in shape, up to 2cm long, grey-green and often flat on the ground. The lovely green and white striped flowers are on stems up to 10cm tall, but they themselves are only 1-1.5cm long. They are held erect on the stalk. Parts of the flower have great names. The green hood, for instance, is called the ‘galea’, and those long ears or wings sitting either side of the galea are called ‘lateral sepals’. And just in case you are wondering, the bump at the stem end of the flower is the ovary. These look absolutely delightful when you find them in the bush…just don’t tread or kneel on them when you go to take a photo!