“Between 11 and 3 stay under a tree” (or “11 to 3, stay under a tree”) is a rhyme about when it’s best to avoid the midday sun. Australia’s Cancer Council issued a poster in the 1980s, “Between eleven and three, slip under a tree.” Variations include “sit under a tree” and “hop under a tree.”
   
“Between 11 and 3 stay under a tree (when sun is high in sky)” was cited in 1996. “The rule is, apply sunscreen, wear a hat and ‘from 10 till 3 stay under a tree’” was cited in 2004.
       
 
National Library of Australia
Title Poster, ‘Between eleven and three, slip under a tree’, colour screenprint, paper, produced by the Ca…
Other Contributors Cancer Council (Made)
Published 19801989
Physical Description Posters
326 mm x 433 mm
Subjects Australia (Place)
Summary
Poster, ‘Between eleven and three, slip under a tree’, colour screenprint, paper, produced by the Cancer Council, Australia, 1980s. Rectangular colour screenprint poster in portrait format. The poster promotes the ‘Slip! Slop! Slap!’ sun protection campaign and is titled ‘Between eleven and three, slip under a tree’. The poster has a blue background and features an illustration of a two bird cartoon characters wearing hats and shirts and standing under a tree. One of the characters is wearing a purple shirt with text on the front “Slip! Slop! Slap”. The other character is wearing a watch. The title is printed above the illustration and text below the illustration conveys the message to protect against sunburn and the possibility of skin cancer by seeking shade in the middle of the day. The producer’s mark is printed in the lower right corner.
         
Google Bpoks
New Scientist
Volume 135
1992
Pg. 9:
“The slogan in New Zealand and Australia to ‘slip under a tree between 11 and 3’ is sound advice,” he says.
 
Google Groups: uk.rec.gardening
Bob Williams
8/22/96
(...)
Between 11 and 3 stay under a tree (when sun is high in sky)
 
Google Books
Life Talk for a Daughter:
Advice on 60 Issues from Passion to Success
By Izabella Little  
Cape Town: Oshun Books
2004
Pg. 134:
The rule is, apply sunscreen, wear a hat and “from 10 till 3 stay under a tree”.
   
Birth.com Forum
bruky
01-11-2005, 12:22 PM
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i will always have that 11-3 stay under a tree rule especially here in ACT, its just too damn hot!! Much better to be inside doing something I think.
     
BritishExpats.com Discussion Forum
Soi Oz
May 28th 2005, 6:44 am
Re: Only Mad Dogs & Englishmen .........
I’m not a mad Englishman, but I wouldn’t avise anyone to go out in the midday sun in summer. Eleven to three, stay under a tree .... unless you like looking like a tomato.
   
Mesothelioma Info
Steps to be taken for Cancer Free Life
Friday, August 19, 2005
(...)
“Between ten and three, stay under a tree” - or better, inside.
     
Geisel School of Medicine at Dartmouth University
Stay Safe on Sunny Days
Spring is finally here, and the Cancer Center’s SunSafe program is a great tool for learning how to minimize the risks of too much sunshine while enjoying sunshine’s welcome goodness.
May 21, 2012
(...)
Avoid or limit exposure during the sun’s peak hours of 11 a.m. to 3 p.m. Try to schedule outdoor activities in the early morning.or late afternoon. Teach your child to seek shade if he or she is outside during peak hours. (“Eleven to three, stay under a tree.”)
   
ITV
11:41am, Fri 12 Jul 2013 Granada Weather and Travel
How to keep cool in the heat
- last updated Fri 12 Jul 2013
(...)
Stay out of the sun during the hottest parts of the day, between 11am and 3pm. The old adage applies “Between 11 and 3 stay under a tree!”