The Garden and Landscape in a Time of Drought and Fire

 By Susan Carter, CSU Extension Tri River Area, Horticulture and Natural Resource Agent

I currently live in Fruita where the Pine Gulch Fire is about 12-15 miles north of me.  This morning I awoke to most of my garden covered in ash. It is amazing how far it travels.  A vegetable specialist from CSU campus suggested hosing off the ash. The plants would not be harmed by a loss of photosynthesis unless the ash layer was thick. By the time I was done hosing off everything, my once clean feet were covered with soot. I also learned that the fire-retardant slurry that fire fighters use, is high in phosphorus, and could harm plants. So how far does this slurry travel? I don’t know.

But the ash also got me thinking about defensible space.  My husband is a retired firefighter EMT of 21 years and fought many wildfires.  He doesn’t seem too concerned about the current situation since it is miles away, but In this time of drought, wildfires could happen ANYWHERE.  We should all be prepared. https://www.ready.gov/

How can you be prepared in the garden and landscape?  I would start by removing any dead plants. Deadhead flowers (removing flower stalks that are no longer blooming) as often as they dry out. Deadheading perennials and shrubs will also help them put more energy back in the root system instead of putting energy towards producing seeds. 

Remove leaf litter that is close to the house or in the gutters. It just takes one ember to land in a crook of the house where there is debris, and a fire starts. You could start a compost pile away from the house to add the plant debris. 

Closest to the house, use rock mulch, flagstone, paver stones, or other non-combustible materials. Keep wood piles and other wood products/furniture away from the house. Ideally a zone of lower growing, high to moderate water-loving plants are closer to your house, as long as it does not affect your foundation. 

To create defensible space, height should increase as you move away from the house. See the Colorado State Forest Service website for more detailed information on Defensible Space. 

https://csfs.colostate.edu/wildfire-mitigation/protect-your-home-property-forest-from-wildfire/#:~:text=Defensible%20space%20is%20the%20area,modified%20to%20reduce%20fire%20hazard.&text=Develop%20these%20zones%20around%20each,buildings%2C%20barns%20and%20other%20structures.

Did you know that there are plants that are more fire resistant?  Of course some of that depends on drought and how much moisture is in the plants. Take a look at the list of fire-wise plants here -   https://extension.colostate.edu/topic-areas/natural-resources/firewise-plant-materials-6-305/ .  Choose plants that do not produce a lot of litter. Aspen trees are a good high-altitude fire-resistant garden choice for the mountains. 

Now let’s talk drought. I have been getting many calls about older trees not doing well.  I know when you live on large properties or up in the mountains, typically there is not a lot you can do other than depend on Mother Nature for moisture. But you could water one or a few favorite, or most important trees. If they are mature established trees, water out twice their height or spread, and give them a deep soak once a month to a depth of 12-18 inches. This will keep them vigorous enough to help ward off insects like bark beetles and borers. Some trees, like pinion pines, might need some insecticide treatments to prevent ips beetle from infesting. When there are epidemics of insects AND there is prolonged drought, the trees are very susceptible to attack. More on ips beetles here -  https://extension.colostate.edu/topic-areas/insects/ips-beetles-5-558/

Pinyon pine with twig or bark beetle damage, picture from Tri-River Area

For trees with lower dead limbs, remove them to decrease fire ladder potential. Prune evergreens when dormant to prevent attracting insects, like bark beetles and borers.  Use proper pruning techniques and cut outside the bark ridge and bark collar.  For bigger limbs use the three-cut method to prevent the limb from breaking and causing trunk damage. Read more about pruning techniques here - https://static.colostate.edu/client-files/csfs/pdfs/613.pdf

Turn these limbs into chips or stack in a wood pile, away from your structures. If the plants are diseased or insect infested, follow appropriate protocol, for that particular issue, to dispose of or prevent any spread.

I hate to say it but I am hoping for an earlier winter, with lots of moisture, to help with the fires and the drought.  We can only do what we can do, the rest is up to Mother Nature.