Specialist in the Diagnosis of Plant Problems in Horticulture, Arboriculture and Agriculture

Useful Information



a. Arborists – What Are They and how do they Vary? What is an arborist? What is a tree service? Is there a difference? Yes! Is there a difference between arborists? Yes, there is a big difference! This paper explains all of this and more and directs you to the appropriate web site where arborists can be found. At the end of the article is some insight and helpful information on how to select a good arborist.

b. Fruit and Nut tree and Vine Pruning: Calendar, Instructions. D. Ellis

Confused about how and when to prune the various fruit, nut and berry trees in your yard?  Take a this “cheat sheet” out to the orchard the next time you do your pruning.

c. Pruning Urban trees: How Much and How Often is Really Necessary? D. Ellis

Urban trees do not need to pruned nearly as often and as much as most people (including most tree services) believe and/or say they do. Realizing and acting on this fact can save you a lot of time and money, and your trees will probably be much healthier and more structurally stable too.

d. Supplemental Irrigation for Established Trees.

Also includes good information for watering trees during droughts.

e. Tree Care Information Brochures

International Society of Arboriculture (ISA) Consumer tree Care Information Brochures. Well illustrated and easy to understand brochures for the general public on many aspects of urban and private tree management.

f. Tree Risk Assessment and Management PDF (opens in new window)

A paper explaining tree risk assessment and management. D. Ellis

Other Information

Drought Help

a. Drought and Landscapes Article

An excellent article (opens in new window) on how to best manage landscapes (including lawns) during drought conditions. Taken from the University of California publication, UCIPM Green Bulletin, August 2015.

b. How Drought Affects Trees

A good article (opens in new window) by Bruce Hagen, retired from the California Department of Forestry, explaining how water stress (such as drought) affects trees.

c. Supplemental Irrigation for Established Trees.

Includes good information for watering trees during droughts.

d. The Future of Coast Redwoods in Bay Area Landscapes.

By John Leffingwell of Hortscience. An excellent article explaining why this high water requirement tree species, native to a small are of the California fogbelt zone along the coast, should in many cases be phased out of landscapes.

Horticultural Myths

a. Horticultural Myth Article

An excellent article by Dr. James Downer, University of California Cooperative Extension Farm Advisor for Ventura County.  Dr. Downer discusses some of the most infamous and trendy myths in circulation today, such as: Soil Microbiology Products (the soil food web, mycorrhizal products and various soil biological controls).  He also touches upon some of the most time-tested urban horticultural legends refuse to die, including my favorite, Vitamin B-1.  Other topics include placing gravel at the bottom of a pot or planting hole to increase drainage, pruning to stimulate growth, toxic mulches, ventilation tubes and tree staking.

Download pdf

Debbie Ellis

b.  Horticultural Myth Web Site

When something seems too good to be true, you can bet that it is NOT true.  As with the cosmetic, diet and vitamin industries, many time and money-wasting myths also persist in horticulture. I started to make a collection and explanation of these myths to add to my web site, and while doing that I came across Dr. Linda Chalker-Scott of Washington State University’s own web page called “Horticultural Myths”. I felt that her information was excellent and so well documented that I could not top it. I contacted Linda and asked if I could add a link to her fine web page, from my web site and she graciously agreed. Linda is an Extension Urban Horticulturist at the Puyallup Research and Extension Center, Washington State University as well as holding several other prestigious university and government positions. Take some time to breeze through her collection of topics and you may be able to dispel some myths you’ve been following – possibly without knowing that these are myths at all!

c. Residential Lawn Improvement  D. Ellis

Are you dissatisfied with the appearance of your lawn?  If so, I have a few tips for you.

living stones

Lithops lesliei venteri

Living stones
Cape region of S. Africa

sedges Sedges:
Background - New Zealand hair:
Carex comans 'Bronze'

Foreground -
Carex albula 'Frosty Curls'

New Zealand

Monstrosus Lophocereus schottii 'Monstrosus'
(syn. Pachycereus s.)