Dead Willows and Poplar tree,

[Trevor Gillbanks 6,846]

My wife and I have taken a bit of time out and have travelled to Napier and then on to Gisborne and then to Tolaga Bay. (let's have no Covid discussion here).

 

We noticed from just outside Napier and all the way to Tolaga Bay there are many patches of dead willow and poplar trees.  These have not been sprayed as there are other trees in these dead zones that are still alive.

I noticed that many of the dead trees have black mould on the trees, however, not all the dead trees have the black mould.

I was wondering if this could be as a result of Giant Willow Aphids (GWA).

We have GWA in Manawatu also, but not so many dead trees.

 

I would appreciate any one who has some knowledge of this, as it will effect bees build up in spring time.

[tristan 4,362]

sounds similar to what they look like up here. 

some get absolutely hammered and others not so much.

[nab 86]

its almost winter. there leaves drop off. ours have. 

willows and poplar are like politicians once established very hard to remove.   

[Jas 438]

I wonder if it could be a combination of sap suckers and drought together pushing trees over the edge . We must be over close to a metre of rainfall in deficit now , over the last 18 months or so. i can drive across swampy gullies that have never dried out before , so the water table will be way down There have been a lot of poplar poles fail up here due to the dry , so will be a replant for them  a bit later . 

[Trevor Gillbanks 6,846]

2 hours ago, nab said:

its almost winter. there leaves drop off. ours have. 

willows and poplar are like politicians once established very hard to remove.   

These are not trees in deciduous mode.  Branches are rotting off and many of them are starting to fall overs.  It is more than winter shedding mode.

 

These trees appear to be 2 or 3 years dead.  There are some live ones amoungst them.  

[nab 86]

they could have been poisoned.

we kill some of the big old ones that are making a mess 

[Sailabee 1,102]

There were whole lines of poplars that died of some lergy around here, used to drive past them most days, and watched from start to dropping to the ground over several years, and the same has happened to pines and macrocarpas - each with a different disease killing them.

[john berry 5,636]

I must've missed your post Trevor.  I'm sure  the drought had some effect but willows and to a lesser extent poplars have been dying in Hawke's Bay from the effects of giant willow aphids for several years. The first tree I ever noticed them on was a really healthy crack willow hanging over my favourite swimming hole and that tree has been dead for two years. I was asked to take part in putting out giant willow aphid parasites this autumn and I sussed out a few sites. One month later when I went to put the parasites out the tree I had picked as the best candidate was still alive but all the lower branches that had been leafy and healthy (and covered in aphids) the month before were all dead. The tree itself was still alive and  being close to the river would not have been affected by the drought. Some varieties of willows are more affected than others and small patches of willows seem to be more affected than the large blocks but they sure ain't doing the willows any good..The aphids were quite late arriving this year and despite what I would have considered perfect conditions the bees did not collect much honeydew from them. Harlequin ladybirds do seem to be having some impact.

[Trevor Gillbanks 6,846]

Thanks @john berry. Your feedback has been about what I suspected.  I hope the trees/areas recover.