Observation of the Week, 9/9/17

This group of Haastia pulvinaris plants, seen in New Zealand by @peter_sweetapple, is our Observation of the Week!

Yes, Virginia, that is a plant! peter_sweetapple, a researcher with Landcare Research in New Zealand, found and photographed these Haastia pulvinaris in the northeastern South Island mountains, where they grow in dry, rocky areas. They grow into large hummocks up to 1m x 1m (these are about 30cm, which Peter describes as “quite small”), and in fact are known as “vegetable sheep” due to stories of shepherds hiking out to them, believing they’d found a lost member of their herd.

H. pulvinaris, along with its genus Hastia, are native to New Zealand and are members of the Asteraceae family, also known as the sunflowers and daisies. Peter tells me that a person can sit or stand on these fuzzy wonders without affecting their form, and he explains their structure thusly:

Each ‘mound’ is a single plant comprised of numerous densely packed stems. Each rounded structure on the plant surface is the tip of an individual stem, with woolly appressed leaves packed tightly around the stem tip. Hairs along the leaf margins give the whole plant a velvety texture. The whole structure is a highly evolved adaptation to cold dry conditions; it prevents moisture loss, which is locked up within years worth of dead leaves still attached to the stems and hidden beneath the outer shell of live tightly packed leaves...I encounter these plants, and several other species of similar form, while out tramping (hiking), usually on multi-day excursions to very remote locations.

For his research, Peter studies “introduced mammalian pests in native forests, particularly herbivores , their diets, impacts and management,” and uploaded this observation via NatureWatchNZ, iNaturalist’s sister site in New Zealand. While he’s fairly new to it, he says “ it’s been interesting to see a bunch of people (mainly colleagues) I know and what they are doing on the site. I’m primarily interested in native Alpine and Forest flora but one local ecologist (literally lives just up the road) posts a lot of weed observation, which has made me look more closely at the local weeds.”

- by Tony Iwane

- Here are all 54 observations of Hastia plants on iNaturalist - they really are remarkable.

- Check out a lengthy (of course) New Yorker article about the impact of invasive organisms (especially mammals) on New Zealand’s wildlife.

- Landcare Research has a nice little NatureWatchNZ video on their website.

Posted on 09 de setembro de 2017, 06:57 PM by tiwane