Whitish discharge from Silver Birch Pruning.

[Treeworld]

Hi, I had a call from a client in the week saying that 2 of the 3 small branches we took off Their Silver Birch is oozing a peculiar white fluid. We did the work on the 21st of Feb and initially it was weeping sap which wasn't of too much concern, I popped round today to have a look and am a bit concerned with the discharge. Does anyone have an idea to what it is and if we should be concerned or leave it to take its cause. The tree in general is in good condition and has a healthy crown when in leaf. I'm thinking perhaps its the soil conditions where it is planted, however it seems strange this is only coming from 2 of the 3 cuts. It is something I have not seen and have done many Birches.

 

Many thanks, Dave.

[Tony Croft aka hamadryad]

the ooze appears to be coming from the upper region of the branch (see cross sectional area) indicating sap flow IMO, wouldnt worry, the whitish appearence is probably being caused by bacterial activity taking advantage of the resource (possibly)

[ecolojim]

the ooze appears to be coming from the upper region of the branch (see cross sectional area) indicating sap flow IMO, wouldnt worry, the whitish appearence is probably being caused by bacterial activity taking advantage of the resource (possibly)

 

I'd agree with Tony. Spent the last fortnight felling on one of Natural England's sights working on mostly birch. They've been absolutely running with sap like a tap, but give it even a few hours and it's gone milky white. Observed on stumps and pruning cuts alike

[Treeworld]

Do you think Tony and Jim that the bacteria are feasting on the sugars etc in the sap and this show is growth of the bacteria in the sap flow? It is reasonably mild so good conditions for them to colonise I suppose. Do you think washing it off with water in a week or so when hopefully the sap has stopped dripping(been 3 weeks now nearly) is a good idea. The client is worried as there is a lot entering into the beds below the tree. I have said I'll try and find out the cause and then deal with it and keep an eye on the tree over the season.

[Tony Croft aka hamadryad]

I seriously wouldnt worry, rain and bacteria will clean up. There may be some cause for concern in a succession basis, but maybe just cleaning off the moist deposits on the cuts would suffice.

[mrtree]

Have you smelt the discharge? Fermented? I also think it is likely bacteria (and a few other microorganisms). You may wish to wash the ooze down as it might stain the tree but I think that there will be no problem with the tree and flower beds.

[ecolojim]

Part of me did wonder if the sugars were crystalising as the liquid evaporated/reduced but I wasn't sure they would be sufficient in quantity?

 

Will get some close photos on Monday... A sample any use?

[Tony Croft aka hamadryad]

Part of me did wonder if the sugars were crystalising as the liquid evaporated/reduced but I wasn't sure they would be sufficient in quantity?

 

Will get some close photos on Monday... A sample any use?

 

thats a fair view, i would not entirely rule out, but suffice to say such freely avaliable rich nutrient resources are seldom missed in nature, which is VERY quick to discover and fully utilise.

[Treeworld]

Cheers guys, just got back from a night out with the boys, puts my concerns to bed. Be good to see your pics if you can get any Jim to compare.

[Matthew Arnold]

Cheers guys, just got back from a night out with the boys, puts my concerns to bed. Be good to see your pics if you can get any Jim to compare.

 

Here are some pics of a Sycamore stump. Taken today.