Yaupon is borderline in upper zone 7. Some cold years it can freeze back. I do not believe it is native to Long Island, but I could be wrong. Goodness, for zone 7 there are SO very many hollies that are better looking than American Holly. Fosters #2 is nice, fast, good berries. Smaller leafed. Nellie Stevens is the default holly planted here. Takes shearing very well, but does get TALL. Look into 'Mary Nell'. Incredible leaf gloss and BERRIES, oh so many berries most years. 'Blue Maid' is a nice very hardy blue holly which grows slowly to 12 feet. It takes its time and will not need much pruning. Castle Wall is a very upright grower. (another Blue Holly). Chindo Viburnum might be worth looking into, if it's hardy in your area. Fast grower, very glossy, no spines. This post was edited by dave_in_nova on Mon, Sep 16, 13 at 9:43

She was probably talking about a fungus disease of the roots, found in the soil. If so, there is nothing you can spray on them. Though these are very tough little plants, your specific site could be problematic. The extension agent should go into further details. By the way, lab tests are available for such disease, also via the extension service. Call them for instructions about how to prepare a sample to send to the diagnostic lab.

I'm not certain, but could it be an Ilex vomitoria yaupon, yaupon holly? It looks like some of the ones that I have growing in my yard.

Thanks