Pear tree question

[ToddG]

I have 4 pear trees that are 3 years old that are growing straight up with very few limbs. They are about 12 ft tall now but only have about 4 limbs. I am afraid to head them bback since they are doing so well. I have tried scoring in the past but didn't have much luck. Do you if I just let them grow, they will eventually start putting out limbs?
Thanks,

 

[Prof.Kent]

Let them grow. Once they hit the tree's maximum height they will branch out. I've never been able to head them off.

 

[ToddG]

Let them grow. Once they hit the tree's maximum height they will branch out. I've never been able to head them off.

Thanks. I will let them grow.