Measuring growth

After a somewhat serendipitous inquiry earlier in the year, we had an interesting day a couple of months ago with a crew of enthusiastic ecologists working with high tech laser scanners. The Arbormetrics team measured the volume of growth in some of the first areas to be revegetated on Wild Wings & Swampy Things, in the early 1990s. Although these areas were originally planted as ‘timber plots’, at quite wide spacings, they have gradually filled in with rainforest species. Visiting wildlife, especially birds, are responsible for increasing the diversity of any plantings and it is particularly obvious when the initial plantings are so widely spaced.

Checking out the edge of a plot and planning the work.

The crew divided up into 3 teams so they could cover the 1994 plantings as well as the 1995 plot which is to the left of our driveway. After the initial inspection it was all carried out very efficiently but still took more than 4 hours.

Setting up the scanner near where the vehicle was parked in our orchard which gave reasonable access to two sites.

The equipment is heavy and awkward to transport on foot and these guys were loaded up with water packs ready for several hours work. We were impressed with the thoroughness of the measuring; the scanner was set up every 10m along a bearing for at least 100m before starting again 10m distant from the last bearing.

Allen and I spent most of our time walking with James and Anthony as they were working through dense undergrowth consisting of three different *Calamus* species. (Wait-A-While). We were both impressed with the techniques these guys had developed to get out of tangles while carrying heavy and very precious equipment. The work takes considerable concentration in order to keep out of the way of the laser beam and maintain accuracy. It means either walking ahead of the beam as the scanner turns or squatting down below the beam when the vegetation is too thick to move through easily. It was a novel experience squatting under a tripod with 3 other people for 46 seconds, I was being very careful not to bump the tripod legs but I was informed that it wasn’t necessary for me to whisper!

This beautiful 4-spined Spiny Orb weaver needed to be relocated after she decided to investigate the scanner more closely.

Jerry and Marcus with the scanner in a horizontal position to get a reading on the height of the surrounding trees. There were two scans taken at every point in dense forest to give an accurate picture of the volume.

After lunch and a short break they packed up their camp equipment and we drove in convoy to a Rainforest Rescue property north of the Daintree River. This beautiful forest contains some spectacular old trees. As the wind had increased after lunch it was decided to set out marker cones and return to the forest in the early evening when it was forecast to be calm.

James, Rob, Marcus and Jerry with Allen at Lot 18

Setting out the cones is, in itself quite a task but makes it possible to carry out the readings at night when the air is usually still. The cones are all labelled so everyone is able to check they are at the correct place.

Putting the cones into the correct order ready for distribution.

This image has an empty alt attribute; its file name is marcus-checking-a-bearing.nef_.jpg — Marcus taking a reading then making sure everyone is in line before putting a cones down. This process repeated every 10m.

Then it was on to check out the next site, have a meal and come back to work at night. Allen and I were happy to head home after a very interesting day.