Friday, March 31, 2017

Strong Winds Need Not Uproot Your Trees!

Tomato cage protecting Catclaw Acacia from being broken by wind but letting it move.

Horrible Winds Ravage Las Vegas! Trees ripped from the ground! 

To watch the news the last couple of days, you'd think this has never happened before. It happens every year. Strong winds whipping through mountain valleys, especially in the Spring is quite common and normal phenomena.  It's what we do to prepare for them, or the lack thereof, that makes the difference between a Spring breeze and a disaster.

There are four things we can do (applies anywhere really) here in the Desert Southwest to keep our trees and the things around them, from becoming a statistic, and possible headline in the news - in a bad way.  Wouldn't it be great if they did a story about a tree that weathered the storm brilliantly and talked to someone who knew about why that was so?



1) Remove all stakes from recently planted trees. Let the tree grow strong by being blown about by the wind. Movement stimulates the plant (all plants) to grow thicker cell walls and to lay down more lignin cells in their trunks and stems. There are ways to make cages that let the trunk move quite a bit, but keep the root ball from rotating or pivoting in the hole. I've successfully used tomato cages that were anchored down on small trees and there are larger ones for larger trees.

If you remove the stakes from a tree and it falls over, it was planted wrong to start with. Dig the tree the rest of the way up, re-dig the hole right and plant the tree right. Before re-planting the tree in the same spot, check to see if it was a good spot to begin with - see #4 below.


2) Water the entire root zone! Do not just put a couple emitters at the base of the trunk. Roots will not grow in dry soil, so you have to apply water at least as far as from the trunk out to the drip line or furthest extent of the tree's branch canopy. If the tree has been butchered and many of the branches have been removed or shortened (probably because it was planted too close to a building, walkway, etc. in the first place), then you need to extend the irrigation out to where the drip line should be for that species of tree or shrub. You can look this up in many books and websites that give details about different plant species. Sunset magazine, your area's university extension service (ours in Las Vegas is University of Nevada), the USDA's NRCS, and some nurseries have excellent information about this.


3) Feed your plants. Leave dead leaves and the smallest branches (twigs) around the bases of the plants so they can decompose and return nutrients and organic matter to the soil in the root zone. Or, if you can't bring yourself to do that, get a leaf vacuum (many are blowers that can be converted with a kit that you buy separately or that comes with them) that sucks the leaves and twigs up, grinds them up and puts them in a bag. Then, spread this ground up mulch (free mulch!) around the tree. Purchased tree bark isn't as good as it doesn't decompose very well especially in the desert, but it's better than rocks. You can also use commercial fertilizer (but please use it with mulch, not instead of it)- read up from the above mentioned sources, especially the university extension services and the NRCS about what different needs different species have. For example, palms need very little nitrogen, but need a lot of potassium and micronutrients.


4) Plant trees smart. Avoid planting them where they will be in the way once they are full grown. The less you 'have' to prune them, the better off they'll be. The above sources talk about the expected height and width of the plant once mature. Sunset is good about adjusting these figures for the desert southwest as many species tend to grow less here, but maybe not as much less as one may think. Plant them also where they will have as much shelter from the prevailing winds as possible. In Las Vegas, the winds swirl a bit, but tend to come from the Southwest in Summer and North in Winter. If there isn't any or much shelter from wind yet, plant several trees - spaced far enough apart so they won't tangle with each other much once full grown - in a windbreak (NRCS has excellent info about this) so that they will create wind protection for other plants in future.

Good sources for further information:

https://www.unce.unr.edu/

http://forestry.nv.gov/ndf-state-forest-nurseries/planting-information-resources/