Felling

 Felling.

One of the troubles with growing Eucalypts is that they can grow very fast. 

Two six year old E. vinimalis blown over winter 2021/2. They have a basal diameter of around 6 inches.

When they are grown amongst other trees they can have root systems not capable of supporting their canopies. They try to get above the other trees and have a high canopy exposed to the wind unprotected by the other trees. If the ground is very wet then the soil has little strength and the trees can be blown over. The situation in the triangular compartment is exacerbated by the high winter water table, which restricts root growth. 

Early 2020  saw storms Brendan, Ciara and Dennis saturate the ground and several of the original Eucalyptus were blown down. The root plate holes were full of water. I had started felling the largest trees for fire wood, but had selected the trees I thought were easiest to fell. At Pit Wood the Eucalypts are in amongst the other trees, and can be very much larger. They risk damaging other trees if they are blown over, or if they are felled. A decision was made to fell larger trees, at least there is the possibility of felling in a direction to minimise collateral damage. 

In the triangular field the largest Eucalypts are from the original planting, so are in recognisable rows and are large enough to need felling. The Eucalypts have strong apical dominance and tend to grow straight up. This means it may be possible to fell in a direction where they will do least damage. When planted in rows it may be possible to fell them all down one side or the other of the row. The picture on the left is of one felled down the middle of the row and balancing on the previously cut stump! 

Because of their apical dominance should they fork then the two limbs grow nearly parallel as in the felled trunk below

The photos above show a forked trunk that has been felled. It can be seen that there is no live wood joining the parts. There is a tendency for one to break in the wind, and then the other. This happened to the post towards the end of the row in the balancing picture above. 

A problem with the different growth rates can be seen in the photo below.

Two Eucalypt pollard stumps can be seen in the front centre of the Photo. They will have been as tall as the as the two Eucalypts with silver trunks and the ones with brown trunks on the far Left at the back. There is a Norway Spruce on the right and a pine stump. These were part of the planting that was mainly felled for the Eucs and conifers to be planted. The Conifers mainly Coast Redwoods are 6-10 foot high while the Eucs were 30-40 ft. The Eucs have been pollarded while they are still relatively manageable and can be felled with little damage to the conifers. They have done their job of providing shelter they now compete with the potential timber trees and will become fuel logs.

Pit Wood History Part II

Pit Wood History Part II 

Planting in  the triangular wood started in March 2011. I had bought some Robinia (also called Black Locust or False Acacia) which I thought were going cheep! There are three large impressive Robinia in Sutton so I thought the climate was OK. They are nitrogen fixers and have a durable timber, so seemed like a useful tree.  There were also a lot of Eucalyptus seedlings, these had been sown and grown under lights over winter. They were in cells and needed potting on. They had been hardening off outside during a mild March and Early April. I decided to plant out rather than pot on. Exactly the same decisions had been made for the same reasons at Cairn Wood in 2010. The result was that a lot of the Eucalypts were not established when there was a sharp frost in May and all the E. nitens, the largest ones needing to be moved on died. A number of other Eucalypts also succumbed to the late frost only a few weeks after planting. I had not learnt  and planted small Eucalypts in April 2011, hoping the lighter soil would allow better root growth. Again all the E. nitens died along with some others but many survived.  

April 2011, the triangular field spot sprayed and  planted up.

There is a ditch along one side of the field, in front of the row of trees, in the top Photo. There was also a single sedge plant towards the corner between the ditch and the track. I assumed that area was the wettest and planted nitrogen fixing alder instead of Robinia and a swamp Eucalypt in the area.

The Triangular field on the 5th May 2011. A sharp air frost has blackened the new growth. The centre row  is ash. The taller trees to the left are Robinia which leafs later. The small Eucalypts to the right were also badly affected. As was the Sweet Chestnut.
  

March and April 2011 were quite after the horrendously cold winter of 2010/11. Trees had flushed early thinking, like me, winter was over. I had planted the whole field by the middle of April.  The -3C frost on May 3rd came out of the blue. The bare rooted trees had to be planted. March is the usual time for spring planting. I can blame the trees for any damage they suffered. The Eucalypts were in cells and could have been potted on or left till mid May. They would have been restricted but alive. A lot of the Eucalypts were lost, The ash and sweet chestnut had their leading shoots killed, so were destined to be forked and poorly shaped trees. Alder are a hardier breed and the Robinia had not come into leaf. The spirals put on to stop the deer browsing kept the frost off the shoots in the spiral.  As there were smaller Eucalypts that had not been planted out I was able to replace losses.

As I write this on 1st May 2022, there are no leaves on any Ash and the Sweet Chestnut is only just breaking bud. (Oak is well out). It has again been a dry warm April, so why the difference I don't know. It could be the micro climate affect of the Spirals. 

There was a fine summer and by August the trees looked well established.

August 17th 2011. The tall trees are Robinia and the dark green showing above black square tree guards are Eucalypts. 

The winter of 2011/12 saw no planting at Pit Wood while  planting at Cairn Wood was completed.  Planting in the Rectangular field waited till 12/13 season. A hay crop was removed from it in 2010, 11, and 12. Meanwhile, the trees grew well in the triangular field except for in an area in the middle of the field.