mdo, I can shed a little light on this: With the Emamectin Benzoate-style treatments available now, tradenamed Tree-age (The 'a' has the two little umlauts or whatever they're called above it, and the word is pronounced like the word triage), it is reasonable to expect two solid years of control from a single treatment, and quite possibly three years. For high-value trees like yours, this seems like a reasonable thing to do. Alternatively, the Imidacloprid insecticides will give a single year's control but are easier to apply. So even that's not a crazy thing to do. Environmentally speaking, either one of these methods is fairly low risk to surrounding organisms, being either injected straight into the trunk, or spread on the ground and soaked in via watering or rainfall, depending on which chemistry you reach for. The other half of your question I can answer too: What seems to happen with EAB is similar to other exotic insect invasions-there is a ramping up period, a period of overwhelming infestation, and then, just as you'd probably expect,a leveling off period after the insects have killed most of their hosts. So if you do happen to save yours during the hot time, you would still need to treat to have the surety of protecting the trees, but overall pressure would level off a great deal. These two lines of thought are straight out of very recent arborist's convention/seminars, so they are up to date. The relevance of this winter's cold temps was also a hot topic (Buh dum bum), but in reality, most thought is that while some of the less-deeply positioned larvae may indeed be killed, EAB has two larval forms and one of them is positioned deeper into the trunk, likely meaning the weather will have fairly little impact one way or the other. We can always hope though! +oM

We don't have EAB here yet, but we do have what are called lilac/ash borers. We have Phaenops gentilis, Chrysophana placida and Agrilus cyanescens. Many non native trees do need help here, but you don't know specifically what to add without a soil test. Unfortunately, they are not free here, but the cost is nominal, maybe $25-30 depending on what you're testing for. I would take soil samples from areas where you haven't fertilized. I just don't see wasting money on additives until you know what's missing from your soil, or what nutrients you already have enough of. I would also be extremely careful with fertilizing right now as we are in severe drought status. If you feel like you need to fertilize before you have soil test results, maybe do half strength. Any problems you're seeing now are most likely drought related as we've had virtually no rain, horrific winds and weeks in the high 90 - 100+ degree temps. We have a 50% chance of rain this weekend, which would certainly help. We've had roughly 4.5" of precip. so far this year. Your soil ph is most likely in the 7 range, as mine is 7.9. I have a Patmore ash, fraxinus pennsylvanica 'Patmore' planted 4-5 years ago and I've not ever fertilized it. It's doing fine. Your ash looks good to me. The native tree choices here are limited which is why we bring in non-natives. FWIW I don't have 10 years experience, just 5, but have planted and killed enough trees that maybe I'm not a newbie anymore, lol. I'm still learning and will be for life. This is a tough place to learn the ropes, but you're doing great. I love your yard! Barb

I vote for Fantex Ash. It goes dormant in winter. Not a single problem frost. It puts on slow to moderate growth, but is not invasive. Nice shade and a very beautiful symmetrical tree. Chinese evergreen ash is also nice. Small leaves but beautiful trunk and nice canopy. The drake variety is supposed to be a faster grower. Also goes dormant in winter and no probs with frost. Can't go wrong with either one.

Some trees may exhibit natural resistance, oikos in michigan was selling seed of an Asian species listed as this: "Fraxinus rhynchophylla Immune to Emerald Ash Borer This is the only ash species left at our farm after the emerald ash borer came and went. I really couldnâÂÂt understand why until I tried to prune a few branches off this species and found even with really good loppers the density and toughness of the wood is quite challenging to clip. ( A lot like pruning apricots. ) I was fortunate to get this seed many years ago from Korea where this mountainous species is found throughout China into zone 5. Ours selections are kind of slow growing compared to green ash but easy to establish in dry or poor soils low in organic matter. Late to leaf missing frosts and completely immune to the borer as far as I am aware. "