“The farmer allows walkers across the field for free, but the bull charges” is a jocular property sign that has been printed on many images.
   
“Notice in a British farm field: ‘The farmer allows walkers to cross the field for free, but the bull charges. Running across this field takes a man 12 seconds. Bull does it in 10’” was printed in the Rock Island (IL) Argus (and other newspapers) on November 10, 1997. “The farmer allows walkers to cross the field for free, but the bull charges” has been reprinted many times, but a second line is seldom used.
 
       
Newspapers.com
10 November 1997, Rock Island (IL) Argus, pg. 1, col. 1:
CHUCKLE
Notice in a British farm field: “The farmer allows walkers to cross the field for free, but the bull charges. Running across this field takes a man 12 seconds. Bull does it in 10.”
 
Google Groups: alt.penpals.forty-plus-yrs
Jolly Olde England (Humor)
Harald Johnson
Nov 13, 1997, 3:00:00 AM
(...)
>Notice in a field: THE FARMER ALLOWS WALKERS TO CROSS THE FIELD FOR FREE,
>BUT THE BULL CHARGES
 
Google Groups: soc.culture.thai
FWD: Mundane words from England..
Char Karnchanapee
Mar 13, 1998, 3:00:00 AM
Subject: Mundane stuff for Monday (fwd)
Date: Monday, March 09, 1998 1:45PM
ODD SIGNS FROM ENGLAND
(...)
12. NOTICE IN A FIELD: The farmer allows walkers to cross the field for free, but the bull charges. 
     
Google Groups: alt.tasteless.humor 
Wednesday June 10, 1998 Issue
Dark Shadow
Jun 10, 1998, 3:00:00 AM
ODD SIGNS FROM ENGLAND
(...)
Notice in a field:
THE FARMER ALLOWS WALKERS TO CROSS THE FIELD FOR FREE,
BUT THE BULL CHARGES
   
Google Groups: alt.fifty-plus.friends
Is this True Bunty:-)
Doug
Jul 12, 1999, 3:00:00 AM
to
>
> Funny Signs in Great Britain: (but could be anywhere)
(...)
> 12. NOTICE IN A FIELD: The farmer allows walkers to cross the
> field for free, but the bull charges.
 
Google Groups: soc.penpals
On the lighter side….....
Lini
Aug 8, 1999, 3:00:00 AM
Funny signs in Great Britian:(but could be anywhere)
(...)
12.NOTICE IN A FIELD: The farmer allows walkers to cross the field for free, but the bull charges.
 
Twitter
Amanda Risi
@AmandaRisi
RT @iandavidchapman The farmer lets you cross his field for free, but the bull charges ♫ ♥
8:36 AM · Jan 3, 2009·Twitter Web Client
   
Twitter
theloon
@theloon
Sign on an Irish gate:  The farmer allows walkers across the field for free, but the bull charges.  #tcot
5:54 PM · Mar 16, 2009·Twitter Web Client
   
Twitter
mark davis
@markdavisartist
Sign on an Irish gate:The farmer allows walkers across the field for free, but the bull charges.
11:29 AM · Mar 17, 2009·Twitter Web Client
 
Twitter
Eshamo
@Eshamo_Noni
Funny sign on a field:
The farmer allows walkers to cross the field for free, but the bull charges.
1:32 PM · Oct 30, 2012·Twitter Web Client
     
Twitter
Gavin Noble
@NobleGavinMr
Saw a sign on a gate that read:
‘The farmer allows walkers to cross the field for free, but the bull charges.’
4:19 PM · Jun 8, 2021·Twitter for Android
 
Twitter
Bernard Cormier
@BernardCormier
PUN OF THE DAY:
The farmer allows walkers to cross the field for free. But the bull charges.
#TodaysPun
6:23 AM · Jun 20, 2021·Twitterrific for iOS