COTONEASTER GLAUCOPHYLLUS & COTONEASTER FRANCHETII ARUNDO DONAX

Both cotoneaster varieties produce large amounts of highly viable seeds, mature quickly, are very long-lived, and form dense (often pure) stands, outcompeting native shrub species in a wide range of habitats.

COTONEASTER GLAUCOPHYLLUS

Spreading evergreen shrub or small tree to 2-5m. It has pale blue-green leaves and erect young stems covered in downy hairs when young which become hairless and dark reddish-purple when mature. Clusters of 15-60 small white flowers appear from October to January followed by scarlet or orange berries (4-7mm) from February to August.

COTONEASTER FRANCHETII

Evergreen shrub or small tree to 3m+, similar stems but with shiny leaves on top and white-grey hairs underneath. Clusters of 7-15 small pinkish flowers appear from November to January, followed by scarlet or orange berries (5-9mm).

ON THE DAY of writing, I was in the township of Milton (cue the ‘Milton in Milton’ jokes). I decided to go for a walk to try and get the blood flow going after a day inside, and found myself – as I often do – clambering through empty lots and sections looking for interesting weeds. I didn’t find too many weeds but I did see some impressive-looking strikes of fleabane.

Fleabane ( Conyza sumatrensis) is a common annual weed found in wasteland areas all over New Zealand, but it’s also becoming a major weed competitor of pastures and orchards in warmer, drier areas. It is originally native to South America, which flies in the face of its scientific name ‘sumatrensis’. It was originally found in Sumatra in Indonesia – hence the name – but was later determined to have come from subtropical South America. Fleabane has now effectively spread to most of the world.

It is a member of the Asteraceae family so its notable cousins include thistles, artichokes, coffee, lettuce and sunflowers. There’s a long history of its use as a flea repellent, but unfortunately I am unable to confirm or deny whether it works as there is no definitive data to show efficacy. I can say anecdotally that I know of a number of people who put dried fleabane stalks and leaves in their dogs’ beds and swear by it, but I am yet to be convinced.

It’s quite a distinctive weed. It begins its life as a small tight rosette, with flat, broad leaves featuring little notched teeth along the sides that point to the end of the leaf. Soon after establishment the plant begins to bolt and produces multiple tall upright stems that are densely covered in leaves. These stems can easily reach 2m or even higher in the right environment.

Soon after, the plant produces an enormous number of very small creamy yellow flowers. These flowers produce a massive number of small fine seeds, each with their own feathery parachute that lets the wind carry them for miles. If one fleabane plant survives to drop seed it can spread over a wide area very quickly. Control of fleabane can take a little work. Animals won’t eat it so they’re no help, and often there is too much to effectively weed it by hand. It isn’t very competitive at young stages of growth so maintaining good dense pastures can help keep it out.

Chemical control can be tricky as fleabane is relatively tolerant of many chemical herbicides. In orchards, glyphosate can be used but only when the plant is in its very young growth stages.

In pasture you can use 2,4D or MCPA but again, these products will only work when fleabane is at the rosette stage. Once it’s too big, you’ll suppress it but you won’t kill it. n