Re: CULT: Leaf Spot-Boron Deficiency?
- To: Multiple recipients of list <email@example.com>
- Subject: Re: CULT: Leaf Spot-Boron Deficiency?
- From: firstname.lastname@example.org
- Date: Tue, 10 Feb 1998 17:03:18 -0700 (MST)
Mike Lowe wrote:
>In the apocrypha of iris literature there is a strong belief, (myth?) that
>iris grown in urban areas where coal smoke is at high levels are usually
>completely free of leaf spot. (could they be referencing 'auld reeky'?)
>My chemistry is not up to the task of enumerating the principal elements of
>coal soot, but I do know that boron is a constituent. Boron is unique in
>that it is required for growth in almost all plants but concentrations only
>slightly higher than required for normal growth are injurious.
I don't know specifically about coal smoke, but general industrial air
pollution has historically been high in sulfur. If leaf spot is caused by a
fungus, this will definitely cut down on its occurrence.
New York, USDA zone 5