A certain ash tree is the center of our backyard garden's universe. Given the spread of Emeral Ash Borer - and the age of the tree - we are likely to lose it sometime in the next few years. Losing the tree would dramatically change the garden conditions, especially for the north side of the garden. I've waffled back and forth as to what is the best thing to do. I've planted a number of smaller trees in the garden beds over the years to provide some shade when the ash dies and have also planted a lot of things that could survive the higher light levels when the tree dies. So, I've tried to cover as many bases as possible and then hope for the best :-)

I think your supposition about the amount of likely change is unduly alarmist, unless one lives close to sea level on a coast. I am secretly relieved that my house sits at 75 foot ASL, which most likely means my own house is safe enough, but all the bayside freeways and international airports may be history without some major system of dikes. I suspect that global climate change is less about consistently higher temperatures year round in all parts of the world, than it will be about more climate variability with both highs and lows more extreme, along with changes in wind and rainfall patterns. Locally here in California so far the changes seem much less extreme than in the rest of the USA, but what changes may occur to our winter mountain snowfall may require major conversion to desalination plants to support current population. I don't foresee suddenly becoming more tropical here, but am designing with more drought and variable temperature tolerant plants in general. If climate change affects ocean currents and water temperatures in a major way, all the world's unique plant communities in Mediterranean Climate Zones are at major risk of being wiped out, as are tropical cloud forests. This may mean that now is the time to visit coastal California's Redwood forests or South Africa's Cape Floristic Province before they are lost in habitat. I suspecr that tropical coral reefs are equally vulnerable.

Typical landscape plants in general, which tend to become popular and broadly useful because they are mostly broadly tolerant of varying conditions; I don't feel as alarmed about. The next 20 years look to be full of unknown surprises, and at least the USA federal policies as promulgated by our do nothing and too reactionary senate in particular, aren't responding to the impending changes. Other countries and individual states seem much more proactive, but quite probably it still isn't enough...

I think your supposition about the amount of likely change is unduly alarmist, unless one lives close to sea level on a coast. I am secretly relieved that my house sits at 75 foot ASL, which most likely means my own house is safe enough, but all the bayside freeways and international airports may be history without some major system of dikes. I suspect that global climate change is less about consistently higher temperatures year round in all parts of the world, than it will be about more climate variability with both highs and lows more extreme, along with changes in wind and rainfall patterns. Locally here in California so far the changes seem much less extreme than in the rest of the USA, but what changes may occur to our winter mountain snowfall may require major conversion to desalination plants to support current population. I don't foresee suddenly becoming more tropical here, but am designing with more drought and variable temperature tolerant plants in general. If climate change affects ocean currents and water temperatures in a major way, all the world's unique plant communities in Mediterranean Climate Zones are at major risk of being wiped out, as are tropical cloud forests. This may mean that now is the time to visit coastal California's Redwood forests or South Africa's Cape Floristic Province before they are lost in habitat. I suspecr that tropical coral reefs are equally vulnerable.

Typical landscape plants in general, which tend to become popular and broadly useful because they are mostly broadly tolerant of varying conditions; I don't feel as alarmed about. The next 20 years look to be full of unknown surprises, and at least the USA federal policies as promulgated by our do nothing and too reactionary senate in particular, aren't responding to the impending changes. Other countries and individual states seem much more proactive, but quite probably it still isn't enough...

I was just discussing this with my mother!

Here in Houston, we are used to year-round wet weather and hot humid summers, but over the past decade as the temperatures have crept up the summers have become hot and dry, and the winters have been wet and milder.

We've been studying what has thrived, and I'm only planting and recommending plants that can survive in both floods and droughts.
I don't believe we're going to have to totally change our plant selection, just tweak it.
More importantly though, I've been advocating things like rain-barrels and dry creeks (which are pretty much unheard of in a place where it used to rain every other day.)

I think the key is to design with the extremes in mind and install more forgiving and hardy landscapes.

Woodyoak, I can absolutely guarantee you that you will NOT lose your ash tree to Emerald Ash Borer if you are willing to invest in 1 to 5 bottles of Bayer Advanced Tree and Shrub systemic (active ingredient imadicloprid) annually. Better yet, buy the generic off brand equivalent if you can find it (some stores carry a brand called Green Light that is about 40% less than the Bayer).

Trees here in Oakland, Macomb, and Wayne Counties in the Detroit area which are now treated annually with imadicloprid are perfectly normal and healthy. Unfortunately, this product was not widely known and only available to professionals when the EAB first came around, so most homeowners' backyard trees and wild/woodland trees died in vast numbers back then. Unless the EAB develops resistance to this chemical there shouldn't be any problem saving trees. The only drawback is cost, a fully mature large tree would cost as much as $100 a year to treat at $20 a bottle -- size determines dosage. The product itself is extremely easy to use, pour into small holes dug at base of tree and water in.

denninmi - I have not been able to convince myself that the treatment is worth it. All the ashes in the backyards here are about the same age/size. A couple of years ago the neighbours to the north's ash came down on a windy summer day - no sign of EAB; just age taking its toll. The neighbour to the south's tree is rotting 6' up the trunk and I fear it will come down soon - on our house if the wind is from the SW (common in summer!)

I've waffled back and forth on this issue but I have come to see the loss of the tree as inevitable soon one way or another, and have tried to prepare for it as best I can by adjusting the plantings. The sooner the tree comes down, the sooner a replacement can be planted and get busy growing. One issue I feel is neglected around here is the need to renew tree canopy. There is an over-emphasis on retaining existing mature tree canopy with little emphasis on adding new 'generational' trees (i.e. ones that take generations to mature). Looking around our 1960s-era neighbourhood I can see that in a few years many of the mature trees will reach the end of their natural lifespan, but most of the trees being planted are smaller ornamental trees because there is not room for big ones until the old ones come down. My main internal debate now re the ash is what is the best tree to replace it with when it inevitably comes down.

A garden is never static. That's one of the joys of gardening.

I had major damage from ice last winter. It has taken me months to clean it up. I garden on about 5 of 10 acres I own. My friends are saying, "Aren't you just sick about all the damage?".
Nope. I look at it as a new design opportunity. Same with climate change, new design opportunities. Ya gotta roll with the punches.
Mike

Brilliant thought, Mike, and transferrable to many other arenas of change.

Karin L