Water off the roof?

grizzlywon

Shohin
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Fresno, CA. Were all the food comes from if we ha
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I have heard that some of you collect rain water off your roofs and use it to water trees.

But then I was recently at Al's house and he mentioned that one of his trees had died because it was getting water directly off the roof of his house and it picked up a disease (please correct me if I am wrong Al).

I have some trees that get rain off my roof and this is starting to freak me out.

What is the issue? Is it just an issue if you have a tree that overhangs your roof, (IE birds are pooping on it) and this is where you pick up a lot of nasty diseases ETC., for your trees? Isn't that were Fireblight comes from?

In my case, I have a tile roof and no trees overhanging the area. Would this make my water pretty clean? Am I okay in this case?

I also think if I just get a gutter installed it will stop the rain from landing in my pots and I can keep my tress in this good area of my yard. I have a small yard, so space with light is at a premium. It will just cost me a little to get the gutters.

This seems like it is going to become more and more of an issue as water shortages become more and more common.

Thanks.
 
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I have heard that some of you collect rain water off your roofs and use it to water trees.



Thanks.

I have used water collected from the roof and stored in my rain barrel for the past five years. My mother actually grew up drinking water collected from the roof and stored in a cistern.

Of course there could be problems but these must certainly be the exceptions.

Elroy
 
The objection I have heard is that the roof builds up acidic pollutants (acid raid), and the first rinsing into your rain barrel yields some pretty acidic water. The old advice is to have a valve in the downspout diverting water to the ground, and only switch it into the rain barrel after a good flushing rain. There are automatic timers sold for this purpose as well. All this is hearsay, and I have no firsthand knowledge. I water with city water, which is soft here.
Rick
 
I would not take chances with my bonsai, because the root zone is so compact and the soil so free-flowing that anything harmful will get right to it. Save and use it in the garden where you have fine soil to filter it and the roots are a lot more spread out. Besides acid rain, there are various adhesives, metals, moss killers and cleaners used on roofs. With your tile roof you'd have a reduced risk of contamination compared to wood or composition shakes.


I have 70+ trees and the amount of water used for them is insignificant in terms of water bills/rationing, even at the high price here of $3.25/CCF. That's still only .005 cents per gallon and not worth the risk for the savings. I they have an outright ban on outdoor watering, I'd try other methods, such as bottling the water that's run to get hot before a shower. I wouldn't think that you would normally
get enough rain during the spring/summer/fall when you need to water most to save it without a huge tank. Ironically, we get 40+" of rain a year so could store plenty of it, and some people do, but then we don't really have to water much except July and August.
 
Grizzlywon, Will you be at the Fresno Bonsai Society meeting on the 13th? We could discuss water catchment there.

I put a 2 stage rainwater catchment system on my greenhouse this fall. The greenhouse has a metal roof so that is neutral. The water is used for my bonsai trees and for the chickens and summer pigs. My trees are very happy so far. No sign of disease. The animals are also healthy and our eggs are fantastic. I am not worried about plant disease. If anything shows up that I can link to the water I will let you know. I think the rainwater is softer than our hard well water. I would be concerned that a direct drip from a composition roof would cause issues. I wouldn't want to feed my livestock water from a comp roof. Tile would be neutral.

We have a deep well that uses quite a bit of electricity($) to pump. Any water collected from the roof is free. I only catch from 1/2 of the greenhouse roof so about a 9'X10' area approximately. I am amazed at the volume of water from such a small footprint. This winter I quickly filled a 80 gallon barrel and the 1000 gallon tank. I need to double the large tank capacity and I am sure I could fill it.

Our house has a high end metal roof so we are thinking of developing extensive rainwater catchment to water our orchard trees. It is an exciting plan.
 
I thought roof water would be a great idea until I read some posts against it. So I just put a large bucket out in the yard to catch the rain water. Let it set, then run it through a t shirt to filter any dirt,twigs, bugs, etc.
 
Hi all, it was not the water off the roof on the plant that was a problem...

It was the plant was too close to the drip line and water from the roof splashed water and soil from the ground on to the tree giving me a soil borne fungus...verticillium wilt. One maple was affected. The other plants, some junipers and elms were not affected.
 
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I thought roof water would be a great idea until I read some posts against it. So I just put a large bucket out in the yard to catch the rain water. Let it set, then run it through a t shirt to filter any dirt,twigs, bugs, etc.

Do you take the T shirt off first?
 
The roof was a bit older, but I used to keep a 55 gal drum at one of the down spouts filled with the shiners I used for fishing, the rain didn't bother them. I think the biggest issue will be with newer roofing shingles is they have an anti algal /fungal built into the shingle to keep them looking prettier longer. Overall it probably wouldn't be a problem if the roofing is aged. As to acid from the rain getting into your rain barrel, if it rains on your bonsai the acid rain is getting into them too. If you have azaleas they most likely will like it.
 
LOL!! Yes I do!Actually it was her T-shirt! Thought it was an old one she really didnt need anymore. Note - Always ask before using one of her "favorite" t-shirts. LOL!! I'm still alive!
 
I would also be careful if the shingles, or any paint that the water crosses, have begun to deteriorate. Some nasty stuff might be released -- heavy metals, what-have-you.

Your tiles, of course, will probably still be around for an archeologist to find in 10,000 years. So if they're clean, you're probably OK, IMO.
 
LOL!! Yes I do!Actually it was her T-shirt! Thought it was an old one she really didnt need anymore. Note - Always ask before using one of her "favorite" t-shirts. LOL!! I'm still alive!

And the big question everyone wants to know "was she wearing the t shirt when you took it off.":D

Yea always ask about those dish towels too. They clean pots really well but mama gets a little bent when she finds her spring tea towels outside with calcium and fertilizer grunge on them:eek:

al
 
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