Report 15. Evaluation of tree species adaptation for alley cropping in four environments in Haiti. B. First year of pruning

Abstract

Tree species were evaluated for their suitability as hedgerows for alley cropping in Haiti. Major criteria discussed in this report are total and leaf biomass production, leaf/stem ratio, regrowth following pruning, and survival. The trial was planted at four sites in Haiti, each representing an important agro-ecological environment: high elevation (1150 m); low elevation, humid on calcareous soil; low elevation, humid on basaltic soil, and low elevation, semi-arid environment. At the low elevation, semi-arid site, the trees had not attained sufficient height for pruning during the period covered by this report. The semi-arid site is not discussed in this report. Sixteen tree species were planted in hedgerows at the high elevation and basaltic sites and 20 species at the calcareous site. Leucaena leucocephala, variety K 636, Leucaena hybrid variety KX3, L. diversifolia, variety K 156, Acacia angustissima, Calliandra calothyrsus, Casuarina cunninghamiana and Gliricidia sepium variety HYB were included at all three sites. Between April 92 and May 93, biomass was harvested three times at the high elevation and calcareous sites and twice at the basaltic site. Only species that had reached more than 50 cm after one year of establishment were pruned. Large differences in annual biomass production were recorded among the species across the sites. The most biomass at the high elevation site was produced by Acacia angustissima followed by three species of Leucaena, Leucaena hybrid KX3 (L. leucocephala X L. diversifolia), L. Leucocephala and L. diversifolia. Leaf and stem production was also greatest in these species. At the calcareous site, total biomass was greatest for L. leucocephala and KX3, followed by L. shannonii and L. diversifolia. Cassia siamea produced a similar amount of leaf biomass as L. shannonii and L. diversifolia. At the basaltic site, the most biomass as L. shannonii and Calliandra calothyrsus. Highest biomass overall was obtained by Leucaena leucocephala and Leucaena hybrid KX3 at the calcareous site, followed by Acacia angustissima at the high elevation site. Those species which produced the most biomass also produced significant regrowth. Several species at each site failed to grow sufficiently to be harvested for biomass. Survival of the high yielding species was excellent. Mortality was observed in many of the less productive species, most notably Desmodium gyroides, which completely died off, the Erythrina species, Acadia melanoxylon, A. mearnsii, Mimosa scabrella, and Cassia emarginata, as well as Acacia angustissim and Casuarina at the low elevation sites and Delonix and Flemingia at the basaltic site. Based upon the various factors considered, especially leaf biomass production, the best performing species at each site may be classed as follows: - High elevation: Excellent - Acacia angustissima; Good - Leucaena hybrid KX3, L. leucocephala, L. diversifolia - Calcareous site: Excellent - L. leucocephala, Leucaena hybrid KX3; Good - L. shannonii, L. diversifolia, Cassia siamea - Basaltic site: Good - L. leucocephala, Leucaena hybrid KX3 These trials need to be continued and additional observations taken. The importance of observing species performance over time is illustrated by the biomass yields at the high elevation site. Initially the most biomass was produced by Leucaena leucocephala, variety K 636. At subsequent prunings it dropped to fourth position, yielding significantly less biomass than did Acacia angustissima. Flemingia macrophylla, on the other hand, yielded little biomass during the first two harvests, but ranked third at the third harvest. Only further measurements will determine whether this species should be seriously considered for alley cropping at high elevation.

Nou te évalye espès bwa pou ranp vivan nan divès zòn nan peyi Dayiti. Sa ki pi diskite nan rapò sa-a se kantite fèy bwa yo bay, relasyon ant fèy ak branch tij, fason bwa yo repouse apre koup la, ak tan yo viv. Travay sa-a te realize nan kat (4) zòn diferan nan peyi-a: sou wotè (1150); sou sòl kalkè nan ba altitid imid, sou sòl bazaltik nan ba altitid imid, ak nan yon zòn sèk. Nan zòn sèk la, bwa yo pat gen wotè ase ki ta pèmèt nou koupe yo pandan peryod sa-a. Sa ki fè zòn sèk la pa antre na rapò sa-a. Sèz (16) espès bwa te plante sou ranp nan zòn sou wotè ak sou tè bazaltik, 20 sou sòl kalkè. Kèk espès tankou lesena K636 (Leucaena leucocephalo, var K636), lesena KX3 (L. leucocephala X L. diversifolia), lesena ti fèy (L. diversifolia, var. K156), akasya (Acacia angustissima) kalyandra (Calliandra calothyrsus), pichpen (Casuarina cunninghamiana) ak piyon (Gliricidia sepium, var. HYB) te simen nan tout sit yo. Ant mwa Avril 92 ak Me 93, nou te rèkoltè bwa yo twa (3) fwa nan zòn sou wotè ak nan zòn tè kalkè-a e de (2) fwa nan zòn tè bazaltik la. Sèl espès ki te grandi plis pase 50 cm nan peryod sa-a te rekolte. Nou konstate gwo diferans nan pwodiksyon byomas ant espès yo nan tout sit yo. Nan sit sou wotè-a, se akasya (A. angustissima) ki te bay plis randman. Apre li, nou te jwenn twa (3) espès lesena yo: lesena ibrid (KX3), lesena K636 ak lesena K156. Espès sa yo te bay plis fèy al branch tou. Sou sit tè kalkè-a espès ki te pwodwi plis byomas se lesena K636 ak lesena KX3; de (2) lòt espès lesena (L. shannonii ak L. diversifolia, K156) te swiv yo. Kaysa (Cassia siamea) pwodwi nan menm kantite fèy ak L. shannonii et L. diversifolia, K156. Nan sit sòl bazaltik la, se lesena K636 ak lesena KX3 ki te bay pi gwo randman. De (2) lòt espès tankou L. salvadorensis ak C. calothyrsus te vini apre yo. Lè nou konsidéré tout espès yo nan twa sit yo, se lesena K636 ak lesena KX3 ki sou sit kalkè-a ki te pwodwi plis byomas. Apre yo nou jwenn A. angustissima ki nan sit sou wotè-a. Plizyè espès pat grandi ase pou nou te rekolte yo. Nou konstate tou ke espès yo ki te bay plis randman te pi byen repouse. Nou pat remake pye bwa nan mitan ranp espès ki te pwodwi plis byomas yo. Kèk pye te mouri nan ranp espès ki pat bay bon jan randman tankou espès eritrina yo (E. indica ak E. poeppigiana), kèk akasya (A. melanoxylon ak A. mearnsii), Mimosa scrabella ak Cassia emarginata. Espès desmodiòm nan (Desmodium gyroides) tè disparèt nèt nan tou de sit li te plante-a. Nou te remake tou angustissima ak pichpen-an (C. cunninghamiana) pat vini byen nan tou de sit ba altitid yo; Delonix regia ak Flemingia macrophylla te pèdi anpil pye nan sit basaltik-la. Lè nou gade faktè nou té konsidere yo, espesyalman pwodiksyon fèy, nou ka klase pi bon espès nan chak sit yo konsa: - Sit nan wòtè: Bon anpil - Acacia angustissima; Bon - Leucaena hybrid KX3, L. leucocephala, L. diversifolia - Sit sòl kalkè: Bon anpil - L. leucocephala, Leucaena hybrid KX3; Bon - L. shannonii, L. diversifolia, Cassia siamea - Sit sòl bazaltik: Bon - L. leucocephala, Leucaena hybrid KX3 Li nesesè pou travay sa-a kontinye. Sa ka pèmèt nou jwenn plis enfòmasyon toujou sou espès yo. Li enpòtan pou nou fè remake ke nan sit sou wotè-a L. Leucocephala var. K636 te pwodwi plis nan premye koup la. Nan lòt rékot ki vin'n fèt, espès sa-a te desann an katryèm pozisyon apre A. angustissima ki vin-n bay plis randman. Se menm jan tou, F. macrophylla te bay you randman fèb nan de premye rekòt yo, men li vin-n pase an twazyèm pozisyon sou twazyèm koup la.