Acorn Strategies How Acorn Size Influences Seedling Size

Acorn Strategies How Acorn Size Influences Seedling Size and Possible Choices

Acorns Sized by Round Hole Screens • Four nurseries in Study – Wilson, JP : Red oak only – Valonia, Penn : Red and white oak • Made as many sizes as possible with round hole screens • All lots floated to remove poor seeds • Planted by hand for precise placement • Fall 2001

Sizing red oak acorns with round hole screens

Sizing red oak acorns with round hole screens

Comparison of largest and smallest acorn

Line up of red oak acorns Largest acorn on left

Experimental seedbeds at the Penn Nursery

Hand planted acorns Measured plot marked with pink flagging held by a nail

2 -0 white oak seedlings at the Penn Nursery

2 -0 white oak, Penn Nursery Larger acorns planted on left Smaller acorns planted on right

Data from Wilson and JP • • • Red Oak only 1 -0 seedlings Wilson 8 sizes and 10 blocks JP 10 sizes and 8 blocks Trees undercut with tractor, lifted by hand, bagged by plot • Measured at Purdue • Plot means analyzed by regression

So What? • Larger acorns on the average give bigger average seedlings. – Aid in getting bigger trees – Tailor fertilizer and water to the acorn size for uniform crop. • Smaller acorns can be stored “on the stump” – Large acorns 1 -0 – Smaller acorns 2 -0

Next Step • • • Size larger seed lots with mechanical sizer Plant larger plots Test how the procedure goes operationally Two more nurseries to lift Take data on white oak JP seedlings have been outplanted – Does this treatment effect field performance?