Guide for Street Trees ( Darwin City Council )

[greysrigging]

Some interesting reading here re our local Council guidelines for planting street trees and in parks and gardens.                                                                                                                                             Cyclone Marcus of March 2018 felled many thousands of old trees throughout the City and in the older suburbs ( with overhead powerlines ), many areas were without power for 5 or 6 days.
Worth a read, particularly those who live in Hurricane/Cyclone prone regions.
https://www.darwin.nt.gov.au/sites/default/files/publications/attachments/trac_final_report-establishing_a_resilient_urban_forest_for_darwin.pdf

[DoomsDave]

YIKE

 

[Silas_Sancona]

14 hours ago, greysrigging said:

Some interesting reading here re our local Council guidelines for planting street trees and in parks and gardens.                                                                                                                                             Cyclone Marcus of March 2018 felled many thousands of old trees throughout the City and in the older suburbs ( with overhead powerlines ), many areas were without power for 5 or 6 days.
Worth a read, particularly those who live in Hurricane/Cyclone prone regions.
https://www.darwin.nt.gov.au/sites/default/files/publications/attachments/trac_final_report-establishing_a_resilient_urban_forest_for_darwin.pdf

Good read, thanks for sharing.  Always interesting to see how different municipalities draw up such recommendations. 

Here, the biggest issue revolving around street tree choices is alot of the big nurseries focus on ( and push like used car salesmen to their clients.  ) tree choices that repeatedly end up being exactly the wrong choices..

Take such things as Palo Verde and Mesquite for example,  every year, particularly during our monsoon season, it is trees like Palo Verde and a an overly planted sp. of Mesquite from South America ( Chilean Mesquite )  that get damaged, or uprooted completely by even moderate high wind events. Still, these sp. are the most widely planted vs. other stuff like native Mesquites ( inc. a thornless selection of Honey Mesquite, Very attractive btw.  ) our native Ironwood, and Texas Ebony..  which rarely if ever suffer serious damage in such weather events.

The main issue with most Palo Verde and Chilean Mesquite is they can grow incredibly fast in a residential or city landscape and often end up structurally insecure. The pruning practices of many landscapers here doesn't help make most trees less damage prone either ( Lion tailing, for example ). In parts of town where people insist on spacious lawns, the frequent water required to maintain that lawn  also puts these trees at risk ( trees don't produce deep roots / anchor in correctly ). Have seen large Palo Verde drop half their canopies like some Eucalyptus sp. in reletively minor spring windstorms outside of monsoon season.  Just in the last week we've had some decent wind events ( still no rain here in Chandler at least ) While the beastly Mesquite in our backyard ( likely a native from central Mexico ) handled both events with no issues ( winds in the 50-75mph range at times in both events ) Palo Verde planted across the street / near the Hospital here / other spots nearby suffered varying degrees of limb damage.  I keep the Chilean Mesq. planted out front trimmed and Don't water it much. Still, I don't doubt it will come down some day simply due to how it grows ( lots of competing branches that don't space themselves correctly )

That said, here has been some movement in the right direction in various cities in / around Phoenix and Tucson in the last several years to promote using the more wind tolerant species instead of those that can end up collapsing completely. 

As a whole, While some willfully still choose to ignore the glaring fact,  consequences of a shifting climate dictate looking for tree choices which will handle more heat / less potential.. or, at least, less predictable rainfall cycles both locally and across the southwest / in California.  Locally, Tucson takes the lead in that respect.  

Recently came across another really informative website ( www. Oaktopia. org. ) discussing the trialing / planting of different Oak  ( Quercus ) sp. out in California, particularly the San Fran. Bay Area. Good read and some interesting points made by the author regarding thoughts on a changing climate, and where we should look to find tree species candidates which should better withstand whatever changes lie ahead.. Interesting how his thoughts parallel many of my own on that subject. 

[DoomsDave]

1 hour ago, Silas_Sancona said:

Good read, thanks for sharing.  Always interesting to see how different municipalities draw up such recommendations. 

Here, the biggest issue revolving around street tree choices is alot of the big nurseries focus on ( and push like used car salesmen to their clients.  ) tree choices that repeatedly end up being exactly the wrong choices..

Take such things as Palo Verde and Mesquite for example,  every year, particularly during our monsoon season, it is trees like Palo Verde and a an overly planted sp. of Mesquite from South America ( Chilean Mesquite )  that get damaged, or uprooted completely by even moderate high wind events. Still, these sp. are the most widely planted vs. other stuff like native Mesquites ( inc. a thornless selection of Honey Mesquite, Very attractive btw.  ) our native Ironwood, and Texas Ebony..  which rarely if ever suffer serious damage in such weather events.

The main issue with most Palo Verde and Chilean Mesquite is they can grow incredibly fast in a residential or city landscape and often end up structurally insecure. The pruning practices of many landscapers here doesn't help make most trees less damage prone either ( Lion tailing, for example ). In parts of town where people insist on spacious lawns, the frequent water required to maintain that lawn  also puts these trees at risk ( trees don't produce deep roots / anchor in correctly ). Have seen large Palo Verde drop half their canopies like some Eucalyptus sp. in reletively minor spring windstorms outside of monsoon season.  Just in the last week we've had some decent wind events ( still no rain here in Chandler at least ) While the beastly Mesquite in our backyard ( likely a native from central Mexico ) handled both events with no issues ( winds in the 50-75mph range at times in both events ) Palo Verde planted across the street / near the Hospital here / other spots nearby suffered varying degrees of limb damage.  I keep the Chilean Mesq. planted out front trimmed and Don't water it much. Still, I don't doubt it will come down some day simply due to how it grows ( lots of competing branches that don't space themselves correctly )

That said, here has been some movement in the right direction in various cities in / around Phoenix and Tucson in the last several years to promote using the more wind tolerant species instead of those that can end up collapsing completely. 

As a whole, While some willfully still choose to ignore the glaring fact,  consequences of a shifting climate dictate looking for tree choices which will handle more heat / less potential.. or, at least, less predictable rainfall cycles both locally and across the southwest / in California.  Locally, Tucson takes the lead in that respect.  

Recently came across another really informative website ( www. Oaktopia. org. ) discussing the trialing / planting of different Oak  ( Quercus ) sp. out in California, particularly the San Fran. Bay Area. Good read and some interesting points made by the author regarding thoughts on a changing climate, and where we should look to find tree species candidates which should better withstand whatever changes lie ahead.. Interesting how his thoughts parallel many of my own on that subject. 

Dang,

Sounds like the playbook for our genius arborists here in La La Ha Ha Bra. It's available, cheap, get it. Other concerns, out the window they go!

So, they plant, in "treelawns" (3 feet or 1 M wide) Liriodendron tulip trees, that eventually get to be about 300 feet all and about 10 feet across the trunk. (Okay, that's back east, but even HALF that size is too big, and they're water hawgs.) Or, the Elephant Flame Tree of Destruction, aka Brachyciton acerfolius, in the same kinds of places. Roots like the Incredible Hulk.

On the other hand, they do manage do something right, like use Lagerstromea indica in treelawns too.

[Silas_Sancona]

23 minutes ago, DoomsDave said:

Dang,

Sounds like the playbook for our genius arborists here in La La Ha Ha Bra. It's available, cheap, get it. Other concerns, out the window they go!

So, they plant, in "treelawns" (3 feet or 1 M wide) Liriodendron tulip trees, that eventually get to be about 300 feet all and about 10 feet across the trunk. Or, the Elephant Flame Tree of Destruction, aka Brachyciton acerfolius, in the same kinds of places.

On the other hand, they do manage do something right, like use Lagerstromea indica in treelawns too.

Agree w/ you on the last part.. there are places that are doing better in promoting trees which are more appropriate for where they'll be planted.  Good example lately has been more demand for Anarcho Orchid Tree ( Bauhinia lunaroides ) locally. Rarely tops 20ft and fits right into smaller yards, like Crepe Myrtles.. Provides nice foliage / flowers but isn't something thats going to build mountains out of your sidewalk, or crush sewer lines with thirsty wooden fingers.. Also takes heat / infrequent water well.   

No matter whiat choice you make, will say, if you're going to buy trees,  go smaller, say 25gal or smaller. Despite what some of the nursery trade cars salesmen preach,  big trees, like the 40-60gal+ sized some insist are the best investment, for the annoyingly impatient / instantly gratified client, are often more of a challenge to establish properly.  Have heard many stories about paying $$$$ just to have the tree die, or worse, get blown over during a storm and cause damage. ( said investment = $$$$$$$ result, lol )

Have never bought anything bigger than a 25, and will not sell anything bigger than that.  A good grower can produce exceptional looking 15-25gal specimens if they know what they're doing.. Palms may differ but I know there have been similar discussions here regarding the size subject  as well.

Absolutely detest Tulip Trees ( Liriodendron), lol.  There was a neighborhood in Cupertino that used them back in the 50s-60s? I think.. anyway, thinking the last ones were removed after they all started dying after being attacked by some sort of leafhopper that would excrete enough " dew" that it would coat the street below, or cars parked underneath, with a wet looking varnish someone could slip on ( did myself while unloading a plant delivery ) Remember seeing the same thing happen to Tulip Trees where i lived in San Jose as well..  Those were removed in the late 80s.

Keeping an eye on a neighbor's Jacaranda..  was big and healthy until this past spring when the top half started dying back..  has continued over the summer. Hope there isn't some new bug in the area