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Thursday - March 18, 2010

From: San Jose, CA
Region: California
Topic: Trees
Title: Fast-growing tree, non-toxic for horses, in Northern California
Answered by: Nan Hampton


Hello..I need to find a fast growing shade tree, native to California (I live in Northern California, south of San Francisco) that would be safe next to (but not in) my horses paddock. Obviously something nontoxic and w/out fruit or flowers that could be toxic to her. Can you help??! I can't find anything anywhere :( :) Thanks for your help!!!


The trees listed below all have rapid growth and are not toxic according to the USDA characteristics links. They all grow in or adjacent to Santa Clara County:

Pinus jeffreyi (Jeffrey pine)  Here is the USDA link to its characteristics.  Here are photos and more information.

Pinus lambertiana (sugar pine)   Here is the USDA link to its characteristics.  Here are photos.

Pinus radiata (Monterey pine)  Here is the USDA link to its characteristics.  Here are photos and more information.

Populus fremontii (Fremont cottonwood)  Here is the USDA link to its characteristics.

Avoid all Quercus species (oaks) and Prunus species (plums, peaches, cherries, apricots, etc.).  Also, do not plant Acer rubrum (scarlet maple) or any Acer species—see Cornell University Plants Poisonous to Livestock.  The pines listed above are not listed on any toxic plant database but Pinus ponderosa (Ponderosa pine) does appear on several of the databases below and should not be planted near cattle or horses.

Here are databases that you can use to check on toxicity of plants to horses and other animals:

Toxic Plants from the University of California-Davis

Pennsylvania's Poisonous Plants from the Universtiy of Pennsylvania

Cornell University Plants Poisonous to Livestock

Toxic Plants of Texas

ASPCA list of Plants Toxic to Horses

Horse Nutrition: Poisonous Plants from Ohio State University Extension Service

10 Most Poisonous Plants for Horses from Equisearch

Populus fremontii



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