Dumping was much more of a problem in 1997, when the open kikuyu-covered banks permitted easy hurling of rubbish right down the bank, including cars.
Litter is also much less now, and stays near the top of the bank, caught by the higher vegetation.
In 1997 - 99 plastic drink bottles lined the gutter along the road at the top of the streambank until stormwater washed them into the stream, where we had to pick our way between the rocks and natural debris to extract them and carry them back up the bank to pile them for collection by Conservation Cleaners, who were contracted to remove these piles along the length of the stream, in addition to large items they hauled or winched out of the stream separately.
Archive observation from 1998:
https://inaturalist.nz/observations/18344095
At that time we requested narrower grilles on the drains along the road, but were told these silt sump entries needed to be wide enough to receive plastic bottles etc in order to keep the streets clean! The prevention of street litter being washed into the stream with stormwater may have been achieved by grilles or other means since that time, or there may be less littering, or perhaps even less use of disposable bottles!
Plastic bags in the trees and on the ground are also much fewer.
For some reason fresh new empty wine bottles appear at least weekly, but at least they are raely broken.
We have been putting such refuse in or beside the rubbish bin which was placed at the entry to the "Native Plant Trail" Bush Path in 1998 to assist the volunteer restoration, and this recently found refuse has all been picked up. (This rubbish bin may be another factor helping reduce litter in the bush and stream).
At the downstream end of the selected Tradescantia Trial Zones, 8-10 car tyres and a couple of wooden pallets were found on the first day of site survey, lightly covered by Tradescantia. These were all dragged to the roadside and picked up the following day by Auckland Council in response to our phone request.
We happened to meet the contractor onsite. He checked that he had all the right stuff, as he had taken the welcome initiative of uplifting a live leafy yucca (vegetative invasion from dumped refuse) that we had uprooted the previous day, as he was aware that they are vegetatively invasive.
https://inaturalist.nz/observations/22344047
[This yucca could have been regrowth from our ad hoc removal during informal survey and yucca-uprooting last year. We placed the removed plant clear of the canopy on the grass verge, hoping a contractor might notice and take it away, but we did not make a service request for pick up of a single plant.
https://inaturalist.nz/observations/17522510
which followed this observation and confirmation of ID in August 2018:
https://inaturalist.nz/observations/15799808]
The prompt and well-informed service in response to our request for pick up of the tyres and pallets immediately improved appearances and gave us a good start with restoration of the Trad zones.
That day or the following one, however, at midday, we noted drooping Mahoe leaves in the interior of this planted roadside "forest". We also found an area of soil uncovered in our initial exploratory Trad removal to be so dry that it was dust, in which a finger could be inserted 5-6mm.
We observed that the mahoe leaf droop was in the area of the car-tyres' removal, where the covering Tradescantia had been completely - and easily - uplifted in removing the tyres and other refuse, leaving about 5x5m of ground bare, exposing superficial mahoe roots previously shaded and kept mopist by refuse and tradescantia.
The area was promptly re-covered with loose Tradescantia, both that removed earlier from the spot, and some more from other areas where cover was not needed.
https://inaturalist.nz/observations/21771487
The two affected mahoe recovered after about 10 days during which it rained twice, the second rain being heavy for a time.
In future dry seasons we will postpone widespread removal of either refuse or ground-covering weeds from areas of surface tree roots. We are also taking this effect into consideration in our Tradescantia removal planning. (See future Posts for more on this observation of Tradescantia removal and drought).
