Climate change and planning for the forest garden

Living near the Gulf Coast and seeing firsthand the impacts of climate chaos on our system (Katrina, Ida etc.) I've been thinking a lot about planning a forest garden specifically with respect to trees and climate change.  Trees are going to be here for 25 years or more, after all.   This part of the world looks to be getting more tropical and more humid, so I'm thinking specifically about looking for trees from one or two hardiness zones south of mine and are a bit more tropical. This does give more range in terms of interesting fruit, but I'm also wondering if I'm signing myself up for more work while trying to get the trees established (and potential loss of plants if we do get some severe winter events.  And then, of course, those choices ripple down to the other layers in the forest garden as well.  Sourcing is also a bit of a challenge because I'm now looking at stuff that would not be carried in my area.  

I'm just wondering if anyone else has given any thought to this issue and what you decided for your forest garden as far as navigating these challenges?

I live in the Pacific northwest and citrus fruits are supposed to be able to over winter here by 2050. This leads to the question do you plant your food forests trees for now what zones you have or baby trees in cold frames and greenhouses till the zones shift to survivable?

I've done a bunch of reading about the possible impacts of climate change and in particular, the "bigger, hotter, colder, more rain, drought" extremes that books I've read regarding the long (very long) history of North America imply regarding the future.

I totally agree with Allen

My only real answer to this is to plant diversity for resilience.

If you have a large enough property to work with, I would think not just in the usual "layers" permaculture talks about, but the layers of plant density and height based on typical wind directions and how extreme wind or extreme water will impact you.

To me, this would be extremely important for the OP, as we're already seeing larger and more frequent big storms. Thinking about berms or hugels that could redirect wind and protect plants would make sense to me.  A strong shrub layer to protect roots of larger trees makes intuitive sense, but I don't know where to look for accurate info. I know that I heard from my friend in Nova Scotia that had a hurricane go through that experts told them that many plants that survived the storm would die over the next decade from the stress. That allowed them to get started on replacements, but it didn't actually explain what could be done proactively.

OT: Building for those extremes so that you and your house survive would also make sense. I was disgusted when I saw the results of one storm on an entire community in Florida - barely a single building was left standing. Clearly, the building codes aren't keeping up and if you are in a position to build or design your own home to withstand whatever nature will throw at it, it might give you peace of mind.

I also live in the Gulf Coast and have for 35 years.  30 years ago we would get a daily afternoon rain shower for about 10 minutes during the hottest mobths; you could set your watch by it.  It cooled everything off.  About every 12 years we would get a hard freezez/ snow.  Now we alternate drought and downpours in the hot months and hard freezes every 3 years but lower total chill hours generally.  I have found that the trees that do not have higher chill needs have adapted quite well with the following methods; plant in semi shade/ among taller bushes when young to shield them from both too much sun/ drought conditions and make it easy to provide ambient warmth from other plants during nights when they need freezes protection.  I also prune them to stay at a height that can be managed in this way.  After they start producing I gradually acclimate them to both sun/ drought and cold and if they acclimate well continue the process and if not I will prune them back to a smaller size.  This has worked well for all citrus, figs; passion fruit.  I have planted my higher chill dependent plants in places that receive winter winds and also part shade and although they still crop it is much less than they did with more chill hours and they require irrigation.  I am thinking the bulk of my future plantings will be very low chill/ no chill as the bones with the higher chill/ specific chill as " treats".  As far as the other plants go, whatever thrives can spread on its own and others can be transplanted to other locations if needed; it does not all have to be worked out beforehand because conditions change from year to year.

I think the biggest think is to limit the amount of rose family trees (dry summer stone fruits, non-native apple/pear/quince, etc) they aren't pest and climate hardy for the gulf states. There are quite a few plants that will do well in zone 8 and 9.

Welcome Alan! So excited to read your book.

My question is about preparing for species (both plant and animal) change due to the changing climate, weather patterns, and even seasonal patterns. I would like to encourage growth of native/endemic species as much as possible, but have been told by longtime residents  that they are having to plant more tropical trees if they are planning for a tree lifespan of 30 or more years, which of course, changes the understory plants and even the pollinators. Any guidance on this issue would be very helpful, thank you!

Candace Chandra wrote:Welcome Alan! So excited to read your book.

My question is about preparing for species (both plant and animal) change due to the changing climate, weather patterns, and even seasonal patterns. I would like to encourage growth of native/endemic species as much as possible, but have been told by longtime residents  that they are having to plant more tropical trees if they are planning for a tree lifespan of 30 or more years, which of course, changes the understory plants and even the pollinators. Any guidance on this issue would be very helpful, thank you!

You raise a really important issue, and there are no simple answers. I have planted a few trees in my neighbourhood, such as buartnuts and heartnuts, that aren't suitable for our current climate but might thrive in a few decades time by the time they are large. The difficult part is that the climate is a complex, unpredictable system and adding more energy to it will have unpredictable effects, not simply raise the temperature by x degrees everywhere. Here in Scotland it's entirely possible that we could lose the Gulf Stream and be left far colder than now. My only real answer to this is to plant diversity for resilience. Plant a few things for expected conditions but don't put all your eggs in one basket and plan your whole garden for a future climate that may never come.