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The University of Tennessee UT Tree Improvement Program

Jason Hogan Major Professors

Dr. Scott Schlarbaum Dr. Allan Houston

October 16, 2013 12:20 P.M. 160 Plant Biotech Building

� � Root Production Method � Multi-step container production method � Emphasizes the root system

� Primarily root volume

What is RPM®

� � Transform taproot into

fibrous root system �  Container Size �  Air root pruning �  Timing

� Higher Survival � Accelerated Growth rate

in field � Believed earlier

maturation

Effects of RPM®

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� � Seed Selection

� Collection � Processing

� Step I � Seeding � Stratification � Germination � Air Root Pruning

� Step II � Transplanting � Processing

� Step III � Transitioning Period

�  Misted 48 hrs. � Transplanting

RPM® Method

� � Seed from

phenotypically superior trees � Target wetter sites � Seed is cleaned � Seed is graded

�  Density gradient �  Weight is most

important

Seed Selection

� � Seeding

� Seed placed in bottomless mesh flat � Growing medium

�  40% Composted rice hulls �  40% Pine bark �  20% Sand �  Fertilizer �  Micronutrients �  Wetting Agent �  Mycorrizae innoculation

RPM® Step I

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� � Air space is most

important

� Media provides 35% air space

� Stratification via cold storage

�  1°C. (34°F.)

RPM® Step 1

� � Timing

� Move out of stratification Feb. 1

� Germination

� Shallow root pruning

�  Force fibrous roots higher on the root collar

RPM® Step II

� � Processed � Transplanted

� Plastic square bottomless pot � Pots measure 3.75 inches

�  Shorter pot improves root distribution

� Transplants set on bottomless benches �  60 days � Air pruning on secondary

lateral roots

RPM® Step II

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� � Transitioning period

� Misted 48 hrs.

� Dibble transplanted into 3 gallon squat pots

RPM® Step III

� � Find seed

source � Collection � Processing � Planting � Lifting � Process � Storage

Bareroot Method

�

� Seed trees

� Quantity

� Ease of collection

Seed Selection

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� � Want large

quantities

� First seed to fall is generally poor

� Pick by hand

� Collected by nets

Seed Collection

�

� Clean seed

� Viability tests

� Prepare seed for storage

Seed Processing

� � Plant at recommended:

� Spacing (species specific)

� Depth (species specific)

Planting

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� � Lifter mounted on tractor � Cut to depth � Lift � Store in cooler

Lifting

� � May separate into classes

� Process and bag

Seedling Processing

� � Store :

� Dark �  40° F � Must keep

roots moist!

Storage

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� Retail Pricing

$44.00 $87.00

$281.25

$0.00

$50.00

$100.00

$150.00

$200.00

$250.00

$300.00

Prem. Reg. Hrdwds Prem. Large Dia. Hrdwds RPM S3-3CG

ETSN ETSN FKN

Cos

t in

Dol

lars

Products

Net Cost Quantity = 25

31%

15%

� Retail Pricing

$87.00 $139.00

$1,125.00

$0.00

$200.00

$400.00

$600.00

$800.00

$1,000.00

$1,200.00

Prem. Regular Hrdwds Prem. Large Hrdwds RPM S3-3CG

ETSN ETSN FKN

Cos

t in

Dol

lars

Products

Net Cost Quantity = 100

12%

8%

� Retail Pricing

$255.00 $410.00

$5,455.00

$0.00

$1,000.00

$2,000.00

$3,000.00

$4,000.00

$5,000.00

$6,000.00

Prem. Reg. Hrdwds Prem. Large Dia. Hrdwds RPM S3-3CG

ETSN ETSN FKN

Cos

t in

Dol

lars

Products

Net Cost Quantity = 500

5% 8%

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� � RPM® survival has been reported at 95%

� Planted with tractor mounted auger or shovel � Less transplant shock � Costly shipping

� Bareroot typically shows 65 – 70% survival � Can be planted with dibble bar � Transplant shock � Less costly shipping

Conclusion

�

Depends on the Customer

Is RPM® The Answer

� �  Clark, Dr. Stacy. "Visual Grading and Quality of 1-0 Northern Red

Oak Seedlings." South Journal for Applied Forestry, 2000: 93 - 97. �  Dey, Daniel C. "Tree establishment in floodplain agroforestry

practices." AFTA. 2003. 102 - 115. �  Forest Keeling Nursery. "Forest Keeling Wholesale Catalog." By

Wayne Lovelace. Elsberry, MO: Forest Keeling Nursery, 2013. �  Lovelace, Wayne. "Root Production Method System." National

Proceedings: Forest and Conservation Nursery Associations. Ogden, UT: USDA Forest Service, Rocky Mountain Research Station, 1999. 20 - 21.

�  Tennessee Department of Agriculture: Division of Forestry. "East Tennessee Nursery Seedling Order Form." Seedling Order Form 2013 - 2014. 2013. http://tn.gov/agriculture/publications/forestry/seedlingcatolog.pdf (accessed October 2, 2013).

References

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� � Photos courtesy of :

�  Forest Keeling Nursery � University of Tennessee Tree Improvement Program � East Tennessee State Nursery

Photo Credits

� � University of Tennessee Tree Improvement Program � Wayne Lovelace, owner of Forest Keeling Nursery � East Tennessee State Nursery � Dr. Stacy Clark; USDA Forest Service

Acknowledgements

� Questions?