Growth-rates of Certain Indigenous Species of Cushion-plants.

Transactions and Proceedings of the Royal Society of New Zealand, Volume 70, 1940-41, Page 25

Growth-rates of Certain Indigenous Species of Cushion-plants. By J. Scott Thomson and G. Simpson. [Read before the Otago Branch, October 10, 1939; received by the Editor, October 18, 1939; issued separately, June, 1940.] There are obvious difficulties in taking records of growth rates of wild plants, and these difficulties are greatly increased when dealing with those from subalpine and alpine areas. It is not astonishing therefore, that measurements of the development of our high-mountain plants are practically non-existent. Advantage has been taken of the successful cultivation of many mountain species in the scree-garden of J. S. T. to record their progress, and the figures given below note the growth rates of 52 plants over a period of three years; 19 species are represented belonging to 9 genera and 7 families and the great majority are cushion-plants. It would be premature to subject the details presented to an elaborate discussion, but it seems advisable to place them on permanent record for comparison with further data that may accumulate. Scree No. Diameters when planted in scree. Diameters after 1st year's growth. Diameters after 2nd year's growth. Diameters after 3rd year's growth. Mean diameter increase after 3 years' growth. Approx. area when planted. Approx. area after 3 years' growth. cm. cm. cm. cm. cm. sq cm. sq. cm. Oreobolus pumilio 8.3 × 4.5 10.8 × 7.6 11.4 × 11.4 11.4 × 12.7 5.65 29. 114. 1. " pectinatus 7.6 × 5.1 10.8 × 7.6 12.1 × 10.2 14. × 15.9 7.65 30. 175. 2. " " 15.2 × 15.2 17.8 × 17.8 20.3 × 21.6 26. × 23.5 9.55 182. 478. 2. Hectorella caespitosa 8.3 × 14.6 10.2 × 16.5 12.7 × 20.3 15.2 × 25.4 8.85 95. 300. 3. " " 19.7 × 16.5 21.6 × 19. 23.5 × 21. 25.4 × 22.9 6.05 256. 456. 201. Drapetes lyallii 10.2 × 17.8 12.1 × 19.7 15.2 × 22.2 19. × 25.4 8.2 142. 378. 199. Anisotome imbricata 14. × 14. 14.6 × 14.6 16.5 × 17.8 19. × 22.9 6.95 153. 342. P.9. Pygmaea pulvinaris 3.2 × 2.6 4.5 × 2.6 6.4 × 3.2 8.3 × 5.1 3.8 6. 33. P.10. " " 2.6 × 2.6 3.8 × 2.6 5.1 × 3.8 5.7 × 5.1 2.8 5. 23. 59.”1. " " 5.7 × 5.7 7. × 6.4 8.9 × 8.3 11.4 × 10.8 5.4 25. 96. 59.”2. " " 4.5 × 3.2 5.7 × 4.5 7.6 × 6.4 10.8 × 9.5 6.3 11. 80. 59.”3. " " 4.5 × 5.1 5.7 × 5.7 7.6 × 7. 9.8 × 8.3 4.25 18. 64. M2.11. " " 8.3 × 6.4 9.5 × 7.6 11.4 × 8.9 11.4 × 8.9 2.8 41. 80. M3.11. " " 5.1 × 5.1 7.6 × 7. 11.4 × 10.2 13.3 × 11.4 7.25 20. 119. M4.161. Pygmaea thomsoni 9.5 × 10.2 9.5 × 10.8 10.2 × 11.4 10.2 × 12.7 1.6 76. 103. M1.15. " ciliolata 9.5 × 12.1 12.1 × 13.3 15.2 × 15.2 15.2 × 16.5 5.05 90. 197. 205. " " 5.7 × 14.6 6.4 × 14.6 7. × 15.9 7.6 × 17.8 2.45 65. 106. D1. Donatia novae-zelandiae 29.2 × 30.5 30.8 × 32.1 33.1 × 34.3 34.7 × 35.6 5.3 700. 970. D2. " " 18.4 × 15.9 20.3 × 17.8 22.9 × 20.3 25.4 × 25.4 8.25 228. 505. 157. Phyllachne clavigera 10.2 × 10.2 10.2 × 10.8 12.1 × 11.4 14. × 11.4 2.5 81. 125. 203. " " 15.9 × 15.9 16.5 × 15.9 16.5 × 17.1 17.8 × 18.4 2.2 198 258. P1.44. Phyllachne colensoi 17.1 × 14. 19.4 × 16.5 23.5 × 20.3 24.1 × 21. 7. 188. 400. P2.44. " " 7.6 × 7.6 8.9 × 8.9 10.8 × 10.8 15.2 × 14.6 7.3 45. 174. P3.44. " " 3.8 × 3.8 3.8 × 3.8 6.4 × 6.4 10.2 × 9.5 6.05 11. 76. P4.44. " " 5.7 × 5.7 7.6 × 7.6 10.2 × 10.8 14. × 13.3 7.95 25. 146. 170. " " 2.9 × 5.1 2.9 × 5.4 3.2 × 6.4 7.6 × 6.4 3. 11. 38. 200. Phyllachne rubra 19.7 × 25.4 20. × 25.4 20.3 × 25.4 20.3 × 26.7 1. 387. 427. 1. Celmisia argentea 31.8 × 24.1 33.1 × 26. 35.6 × 30.5 39.4 × 36.5 10. 600. 1128. 2. " " 20.3 × 12.7 21.6 × 14. 22.9 × 15.2 25.4 × 17.8 5.1 201. 354. 3. " " 12.7 × 5.1 14. × 6.4 15.2 × 7.6 17.8 × 8.9 4.45 51. 124. R.6. Raoulia eximia 12.1 × 10.2 12.7 × 10.2 14.6 × 10.8 15.2 × 11.4 2.15 97. 136.

R.8. " " 2.6 × 5.1 2.9 × 5.4 3.8 × 7. 5.7 × 7.6 2.8 10. 34. R.11. " " 14. × 16.5 15.2 × 17.8 19. × 20.3 20.7 × 21.6 5.9 181. 353. R.29. " " 1. × 1. 2.2 × 2.2 3.5 × 3.8 5.1 × 5.1 4.1 0.8 20. R.57. " " 15.2 × 10.2 15.2 × 11.4 15.2 × 12.7 15.9 × 12.7 1.6 122. 158. 150. Raoulia rubra 2.6 × 3.8 2.9 × 4.1 3.2 × 4.5 4.5 × 5.7 1.9 8. 20. R.12. Raoulia buchanani 10.8 × 12.1 11.4 × 12.7 12.7 × 12.7 13.3 × 14.6 2.5 102. 152. R.13. " " 12.1 × 10.2 12.7 × 10.2 14. × 10.8 15.9 × 13.3 3.45 97. 166. R.14. " " 7.6 × 5.1 8.3 × 5.4 8.9 × 6.4 10.5 × 7.6 2.7 30. 63. R.15. " " 12.7 × 8.3 14. × 8.9 15.2 × 10.2 17.8 × 12.7 4.75 83. 178. R.16. " " 11.4 × 8.3 12.1 × 8.9 12.7 × 10.2 15.2 × 11.4 3.45 74. 136. R.18. " " 8.9 × 10.2 8.9 × 10.2 9.5 × 10.2 10.8 × 11.4 1.55 71. 97. R.19. " " 4.5 × 4.5 5.1 × 5.1 7. × 7. 7.6 × 7.6 3.1 16. 45. R.20. " " 8.9 × 5.1 8.9 × 5.7 10.2 × 7. 10.8 × 7. 1.9 35. 59. R.21. " " 7.6 × 5.7 8.3 × 5.7 8.9 × 6.4 10.2 × 7.6 2.25 34. 61. R.23. " " 17.1 × 29.2 17.8 × 30.5 19. × 31.8 21. × 33.7 4.2 392. 557. B.3.129. Raoulia bryoides 5.7 × 5.7 5.7 × 5.7 5.7 × 5.7 6.4 × 6.4 0.7 25. 32. 23.1. Raoulia hectori 7.6 × 5.1 8.9 × 5.7 8.9 × 8.3 14. × 14. 7.65 30. 154. 23.2. " " 5.1 × 2.6 7. × 3.8 7.6 × 4.5 10.2 × 10.2 6.35 11. 82. 23.3. " " 8.3 × 3.8 8.9 × 4.5 10.2 × 5.1 11 4 × 8.9 4.1 24. 79. 8.1. Raoulia hectori var. 6.4 × 7.6 7.6 × 9.5 7.6 × 11.4 11.4 × 14.6 6.0 38. 131. 8.2. " " 4.5 × 3.8 5.1 × 3.8 5.7 × 5.1 9.5 × 7.6 4.4 17. 57.