Grass(?) growing in new thatch

[miketheboilerman]

Hello everyone,

First post here. I've been in my charming little hovel in Wiltshire for two years now. It was built in 1700 with a lovely thatched roof.

Back in November my neighbour and I had the ridge re-thatched with new combed wheat and the main roof areas 'dressed'. Recently we've noticed what appears to be grass sprouting and growing in the new combed wheat. Unfortunately our thatcher is not a great communicator but we knew this at the start, and he did some good work on both our properties 20 years ago.

So, my questions are, is this normal on new combed wheat thatch or is it something we should worry about? Should we get something done about it or will it fade away once the spring arrives and hopefully the sun? Is it really likely to be grass or is it perhaps the combed wheat sprouting?

Any advice from seasoned thatch-dwellers most welcome. Two photos inserted, hopefully.

Many thanks.

 

[worms]

I know less than nothing about thatching and only slightly more about wheat and straw.

Your picture looks to me like wheat seeds sprouting in the damp straw and not unlike what you get at field margins where the straw has been compressed by the combine harvester's wheels rather than going through the thresher. I see that "combed wheat straw" uses a combing technique rather than threshing to remove the seeds (so as not to damage the straw) and I wonder if in fact your straw was very poorly combed, leaving many of the seed heads intact.

What to do about it? Personally I'd get up there and give it a spray with round-up to kill the growing wheat - you probably don't want to wait until it all dries out in spring, as by then you could have a lot of new vegetation (and roots) that will potentially add a mulch layer on top of your thatch. But bear in mind that I know absolutely nothing about thatch!

 

[miketheboilerman]

I know less than nothing about thatching and only slightly more about wheat and straw.

Your picture looks to me like wheat seeds sprouting in the damp straw and not unlike what you get at field margins where the straw has been compressed by the combine harvester's wheels rather than going through the thresher. I see that "combed wheat straw" uses a combing technique rather than threshing to remove the seeds (so as not to damage the straw) and I wonder if in fact your straw was very poorly combed, leaving many of the seed heads intact.

What to do about it? Personally I'd get up there and give it a spray with round-up to kill the growing wheat - you probably don't want to wait until it all dries out in spring, as by then you could have a lot of new vegetation (and roots) that will potentially add a mulch layer on top of your thatch. But bear in mind that I know absolutely nothing about thatch!

Thanks worms.

This makes a lot of sense. I'll see what I can do about getting up there with a sprayer!

 

[88v8]

In the good old days, before the advent of wire and machine combing, rats used to tunnel through new thatch in search of the seeds. Eventually their tunnels led to sinkings in the thatch.

Below, an ultimately unsuccessful attempt to repair a historic sinking, subsequently eliminated at the next re-ridge.

Pre-wire, the maintenance of thatch must have been pretty much an annual task.
Ironic nowadays, that it existed as a cheap method of roofing.

Ivor

 

[Cubist]

Hey Mike and Welcome to the Club,

I had the ridge of Fircroft replaced last March with Combed Wheat and the Water Reed main roof dressed as well. During this an unsightly spread of moss/lichen on the rear of the main roof - North Facing and tree shadowed - was removed. Whilst I have, on other peoples thatched roofs, seen the odd weed or two growing amongst old well established lichen/moss and around their chimney pots I have never come across what you are seeing. Throughout last year there was no evidence that the plentiful quantity of wheat seed present in our new ridge had germinated to produce new growth despite the fair and damp weather we all experienced.

What I find puzzling about the growth on your roof is that its a really funny time of year for any plant to be sprouting - are you domiciled in the Channel Isles by any chance?

Commonly at this time of year most everything has moved into its dormant period for the winter months to be ready for the spring. Global warming may have a bearing but that, to my mind, is a bit of a stretch. The only rationale that makes sense to me is that some wheat stocks are bred for harvest in the winter months and are perhaps much hardier than the typical varieties. Alternatively, as I understood it while talking with our thatcher, a great deal of the straw/reed used in the UK is imported from as far afield as Asia and may have spent months stored and transported in dry shipping containers.

Frankly, at this stage I would be tempted not to worry too much. As you will know, the purpose of the root structure of any plant is to seek out water and other nutrients to fuel the growth of their above ground foliage. Whilst there would be plenty of water available in your ridge, the quantity of available nutrients would be very limited and likely to wash out of the new straw very quickly. As a result I would expect the new growth you are seeing would be poor and likely to be vulnerable to frost. In my view theres a good chance it will die off and blow away before the spring.

That said, if after a few more weeks it looks like a lawn-mower may be needed, then Worms suggestion may be best.

 

[worms]

Cubist, interesting that you had lots of seeds in your thatch but no germination.

With regard to "winter wheat", this is planted in the autumn and will germinate before the coldest parts of winter, giving plants similar to what is on Mike's roof at this point in the year. It is then poised to grow rapidly as spring advances and will ripen earlier in the summer than crops planted in the spring. This is of huge advantage where seasons are short and autumns too wet for reliable combine harvesting. It survives reasonable frosts and it is increasingly common to see crops of winter wheat well into Aberdeenshire and Highland. I'm not sure whereabouts Mike is, but with the added benefit of some bottom warmth coming up from the house, I think it would be a forlorn hope that the frost is going to see it off.

At college we were taught that if winter wheat was growing too strongly over winter, it was worth giving it a light grazing with sheep...

 

[Cubist]

Cubist, interesting that you had lots of seeds in your thatch but no germination.

With regard to "winter wheat", this is planted in the autumn and will germinate before the coldest parts of winter, giving plants similar to what is on Mike's roof at this point in the year. It is then poised to grow rapidly as spring advances and will ripen earlier in the summer than crops planted in the spring. This is of huge advantage where seasons are short and autumns too wet for reliable combine harvesting. It survives reasonable frosts and it is increasingly common to see crops of winter wheat well into Aberdeenshire and Highland. I'm not sure whereabouts Mike is, but with the added benefit of some bottom warmth coming up from the house, I think it would be a forlorn hope that the frost is going to see it off.

At college we were taught that if winter wheat was growing too strongly over winter, it was worth giving it a light grazing with sheep...

Coo, now you've got me worried Worms... I thought I had enough troubles with the occasional squirrel using the roof as a highway between our trees and perhaps taking up residence to save its little legs - hence the most recent pruning/pollarding activities around here... but now I have to be concerned about sheep getting up there ???? Ah well, maybe I can just count em and drift off into blissful ignorance.