Subject: Re: Fertilizing a 100 years old sugar maple?
From: "Don Chapman" <don@bio-organics.com>
Organization: bio-organics supply center
Date: 26 Sep 1997 17:21:03 GMT
Message-ID: <MOD$970926.7240@rec.gardens.ecosystems>
References: <MOD$970923.29264@rec.gardens.ecosystems> <MOD$970925.14740@rec.gardens.ecosystems>



Todd M. Bolton wrote in article
<MOD$970925.14740@rec.gardens.ecosystems>...
>
> The arborist is probably correct about nutrient needs of the trees, but
> I would also have a soil test done. Often soil ph will limit hte amount
> of Iron and trace minerals that the tree can get from the soil. In this
> case adjusting the ph, through the addition of lime to make it less
> acidic,(the more common problem) or (is it?) aluminum sulfide to lower
> the ph may make these minerals available to the tree. The arborist
> should be able to tell you where to get a soil analysis done.
>
>

I'm not sure about this approach for a mature tree. Trying to play with pH
levels on a big scale is risky, and if someone happens to overdo some
chemistry the tree may be harmed. The fact that a tree is mature is a
pretty good indication that it is reasonably well-suited to the soil
conditions.

A safer and gentler approach is to use compost as a mulch.

I'd also not be inclined to take the advice of an "arborist". I know quite
a few of them, and maybe one in five really knows much about soils. Most
are tree trimmers or removers. Be sure to get a second or third opinion
before pouring chemicals around a valuable old tree.