1. The Effects of Scarification On Kentucky Coffee Tree Seeds
Bobby Nance
HORT 2244

2. Gymnocladus dioicus
Landscape value: great for large areas like parks or golf courses
60 to 75’ in height 40 to 50’ in width
Propagated by:
Seeds, cuttings, and grafting
Rich moist soil, zones 3-8
Known to handle:
Drought
Urban conditions
Full sun

3. Scarification
Scarification is the cutting of the seed coat using abrasion, thermal stress, or chemicals to encourage germination
Basically, used to knock through the seed coat with the goal of imbibing the seed with water to promote germination
Methods of scarification used in my project:
Sulfuric Acid treatment: 4 hour soaking duration
Heavily sanded treatment using 100 grit sandpaper
Lightly sanded treatment using 100 grit sandpaper
Moderately sanded treatment by rubbing on coarse cement
One group of seeds was left unscarified as a control group

4. Sulfuric Acid Treatment
Duration: 4 hours
Triple rinsed afterwards
Employed with 4 seeds

5. Sanding Scarification Treatment
2 seeds: 100 grit sand paper
-One heavily sanded
-One lightly sanded
Rubbed against coarse GH
cement floor:
-One moderately sanded
Determined heavily, moderately, and lightly on the amount of endosperm exposed through the seed coat

6. Sanding Treatment
From left to right: the seed that was heavily sanded exposing much of the endosperm, the seed that was lightly sanded showing minimal exposure of the endosperm, and the seed was coarsely sanded using the rubbing technique against a coarsely textured surface exposing a moderate amount of the endosperm.

7. The Set up 4” Pots -Each labeled with corresponding contents Media:
-75-85% Canadian sphagnum peat moss
-horticultural grade perlite
-dolomitic limestone mix
(aka- #1 Mix in GH)

8. Progression: Control Group
Surprising results for being unscarified. Seed coat is very thick and hard.

9. Progression: Sulfuric Acid
Expected results from scarified seeds by sulfuric acid

10. Progression: Heavily Sanded
Had not germinated on first check up, very slow results, showed less growth than control and sulfuric acid treated group

11. Progression: Moderately Sanded
Not very impressive results

12. Progression: Lightly Sanded
Comparative results to heavily sanded

13. Results: The better Performing
Sulfuric Acid Treated
Control

14. Results: Low Performing
Heavily Sanded
Moderately Sanded
Lightly Sanded (best of three)

16. Conclusion
Better early vegetative growth gave rise to better root growth and vigor, based on IAA theory from Plant Propagation Lecture.
Showing the movement of IAA an auxin to the roots. Supplementing the conclusion that greater foliage development can lead to a more extensive root system (Harris, Cuttings 3 Lecture).

17. What was learned?
I learned that it was possible to propagate Kentucky Coffee Tree seeds without scarification at all, which I thought was impossible. I also learned that scarification by sanding is not very effective and that scarification by sulfuric acid can show favorable results.

18. References http://plants.ces.ncsu.edu/plants/all/gymnocladus-dioicus/
Dirr, Michael, and Charles W. Heuser. The Reference Manual of Woody Plant Propagation: From Seed to Tissue Culture. Portland, OR: Timber, Print.
Harris, Roger. "Cutting Propagation." Plant Propagation Lecture. Virginia, Blacksburg. 19 Mar Lecture.