Best-Bet Agroforestry and SoilConservation·Practices

34 Pages·2010·1.45 MB·English

• AcS-o'f.7
MAFE Booklet Series No. 1: fI3~~2-
Best-Bet Agroforestry and
Soil Conservation·Practices
(2001 EDITION)
TABLE OF CONTENTS
CHAPTER 1: CONTOUR RIDGING USING THE LINE LEVEL 3
Figure 1:Equipmentandpeopleneededtomarkcontour
lineswithalinelevel 4
FigureZ: Usingthelinelevelinthefieldandreadingthe
bubbleso thatitisdeadcenter 5
Figure 3:SmoothingtheContourLine 6
Figure4:Aligningridges betweenpeggedcontourlines,
tophalfto theupperpeggedline, thebottomhalftolowerline 7
CHAPTER 2: VETIVER NURSERIES AND CONTOUR HEDGES 9
Figure5: Trimmingvetiverinthenursery 11
Figure 6: Diggingclumpsin thenursery 11
Figure 7: Trimmingclumpsandsplitting 11
Figure8: Plantingvetiveron thecontour 12
CHAPTER 3: TREE NURSERY MANAGEMENT 15
Table 1: TreatmentandNurseryTimes forCommon
AgroforestryTreeSpecies 17
CHAPTER 4: HOMESTEADTREE PLANTING 19
Table Z: Commonnon·fruittreespeciesforHomestead
Plantingandtheiruses 24
CHAPTER 5: UNDERSOWING TEPHROSIA VOGELIIWITH MAIZE 27
CHAPTER 6: DISPERSED SYSTEMATICTREE INTERPLANTING 33
Figure9: Resultsafterthinning(from IOx5mto 10xl0m
and IOx20m) 35
Table 3: Thinningregimeaftertheinitial lOx5mspacing
with200seedlings/ha 35
Figure 10:Pruninga youngtreetoimproveitsgrowthform 36
1
ACKNOWLEDGEMENTS
ThisbookletwasproducedbytheMalawiAgroforestryExtensionProject(MAFE)through
a Cooperative Agreement between USAID and Washington State University under the
DepartmentofLandResources Conservationin theMinistry ofAgricultureandIrrigation.
The collaborationofthe Forestry Departmentis gratefully acknowledged. The authors are
responsible for the views expressed in this bookIet. They do notnecessarily conform with
those of USAID. Much of the information reflects knowledge gained from field-level
experienceswithfarmersoverthepast8yearsbyMAFEanditsmanypartners.Therearetoo
manypeopletothankindividually, buttheircollaborationisgreatlyappreciated, especially
agricultural and forestry staff in government. We also wish to thank individuals and
institutionsforpermissiontoreproduceillustrationsfromthefollowingbooks:AFieldGuide
toLengweNationalPark(1984)byB.Y.SherryandAJ.Ridgeway; Trees ofKenya(1989)
byT. Noadand A. Birnie; Common Fuelwood Crops by E.L. Little, Jf.; Trees ofSouthern
Africa (1977) by K. C. Palgrave; Useful Plants ofMalawi (1975) by 1. Williamson; A
Selection ofUseful Trees and Shrubs for Kenya (1992) by ICRAF; and On-Farm Tree
NurseriesbytheKenyaWoodfuelDevelopmentProgramme.Eachisacknowledgedwhere
used.
ProperCitation: W.T. Bunderson, Z.D. Jere, LM. Hayes and H.S.K.
Phombeya(November 2001). Best-BetAgroforestryand
Soil Conservation Practices. Malawi Agroforestry
Extension Project, Publication No.43, Lilongwe.
,Key individuals involvedinproducing this bookletinclude:
Assistance in Editing
and Formatting: D. Hardesty, D.L. Whaley
Illustrations: F. Bodnar, D. Chimutu
Photographs: W.T. Bunderson, LM. Hayes, Z.D. Jere, lC. Noel,
D. Hardesty, S. Minae andW.A. Bromley
Manuscript Review: R.J. Mwakalagho, N.J. Mu1enga, A.R. Saka and
H.P.P. Chinkbondo
CHAPTER 1: CONTOUR RIDGING USING THE LINE LEVEL
Ridgesalignedwiththecontour
Contour ridge your farm to:
.. reduce water run-off and soil erosion
.. conserve soil moisture for plant growth
.. Improve crop yields
.. Increase ground water supplies
.. reduce siltation and flooding
3
.'~-------'
Introduction: Annual ridging by hand
hoe is the common method ofland
preparation in Malawi. Sincefewfarmers
cultivate on contour, ridges tend to
channel water, which aggravates runoff
.' ' -'l
and erosion. Contourridging reduces
these problems. To dothis, contour
~~~
marker ridges are built as guides to re
align planting ridges. Marker ridges may
be constructed anytime in the dryseason
A C B
afterharvest. Planting ridges are then re
aligned when preparing land for next
season's crop.
Constructing marker ridges
with a line level:
A line (spirit) level isasimple instrument
for marking contour markerridges. It
consists of aspirit level that hangs from a
figure 1: Equipmentandpeopleneeded
taut string between two poles. tomarkcontourlineswith alineleve/.
Note thatmakingthegrooves on the2
Materials Required: line level, Sm sticksatexactiythesameheightis critical.
string, 2 straightpoles or sticks 1.6-2 m
long with flat ends, panga, pegs,
hammer/stonefor driving in pegs, and 3 4. Two people setthe sticks on alevel
people (Fig. 1). surface (e.g., floor) with the string
tight. Markthe exactpositions of
Equipment Set Up and Testing: the 2 sticks on the floor. Then read
1. Trim the ends ofthe sticks to make the line level. Switch the positions of
them flat. Then stand them upright the sticks and read the level again.
on level ground, preferably the floor
5. Ifthe bubble is notperfectly centred
of abuilding. Cut agroove around
both times, check that (a) thefloor is
each stickat exactly the same height
level, (b) the groove heightsofboth
above the ground (about 1.2 to 1.6
sticks are identical, and (c) the level is
m or chest-level to make reading
hanging properly. Correct any
easy).
problems as needed.
2. Tie 2 knots in the centre ofthe
6. Ifthe checks above are correct, the
string, and hang the level between
line level must befaulty and needsto
them to stop itfrom sliding.
be replaced.
3. Tie the string ends in the
groove of each stick.
Using the level in the field 6. FollowStep 4. When the bubble is
(see Fig. 2):
perfectlycentred, insert anotherpeg
atA's position.
1. Start pegging atthetop ofthefield
about 10-20m belowthe upper 7. Repeatthe above steps, inserting
corner. pegs at each pointtill the end ofthe
field is reached.
2. Insert a peg to locatethe starting
point ofXs stick. Avoid placing the 8. Theteam then moves downslope
sticks on rocks, ridges and anthills, or from thefirst contour line. The
in holes and depressions. interval depends on the slopeofthe
field, i.e. 20m apartfor gentle
3. Cinstructs Bto move 5 malong the
slopes, 15m apartfor medium
estimatedcontour line with the string
slopes and 10m apartforsteep
tight.
slopes. Pegging ofcontour lines
4. Creadsthe position ofthe bubble. should coverthewholefield.
He/she instructs Bto move up or
NOTE:When pegging across paths,
down the slope until the bubble is
gullies, anthills, streamsand the like,
preciselycentred. Insertanother peg
shorten the string to halfits length
atthe precise location of B'sstick.
(about 2.5m) to decrease the pegging
5. Leaving Bin place, Amoves past Bto intervalfor greateraccuracy.
locatethe next peg. C instructsAto
move up ordown the slope while
reading the line level.
figure2: Usingthe
linelevelinthefield
andreadingthebubble
sothatitisdeadcente
."
B
5
Smoothing Contour Lines: Pegged When not to smooth the
contour lines maybe smoothed outto contour line: Do notsmooth the
reduce sharp angles between pegs. This contour lineon irregularterrain as it
simplifies the construction of marker could cause runoff problems.
ridges and re-alignment of planting
ridges. Building marker ridges: Build the
pegged contour line into aridge. The
When to smooth the contour
marked ridges simply serve as guides to
line: Smooth pegged lines only on
re-align planting ridges and need not be
uniform terrain by moving certain
biggerthan otherridges ifthey are clearly
pegs in orout ofthe contour line as
marked.
follows (see Fig. 3):
A. Threepeople each stand by thefirst Re-aligning crop ridges: After
three pegs in the line (pegs 1, 2 and
marker ridges are built, align crop ridges
3). Movethe middle peg (no. 2) so parallel to them. Usetwo marker ridges
that all 3pegs are in astraight line.
to align the enclosed area between them.
B. All three people then move two pegs To improve re-alignment on contour,
forward Le. to pegs 3, 4 and 5. align the top halfof the area with the top
Movethe middle peg (no. 4) so that markerridge, and the bottom halfwith
pegs 3, 4 and 5 are in astraightline. the lower markerridge (see Fig. 4)
Repeatthis process till the line is
finished. The line will now be
smooth, following the gradual curves
ofthe contour.
2A
2B ,.;', 3
4A ;fiiij;'-
:.~<~~o<.~~~
.. {".,
Figure 3: SmoothingtheContourLine
Figure4:Aligningridgesbetweenpegged
contourlines, tophalftotheupperpegged
line, thebottomhalftolowerline
imeframe for Contour Ridging
.. JUNE-SEPTEMBER: After harvest and clearing, peg contour lines using a line
level and construct marker ridges
.. AUGUST-DECEMBER: Re-align crop ridges when making new ridges for the
coming season
7
CHAPTER 2: VETIVER NURSERIES AND
CONTOUR HEDGES
AwellestablishedcontourVetlverhedge
Plant contour Vetiver hedges to:
.. reduce surface run-off and soil erosion
.. increase soil moisture and crop yields
.. supply thatching, mulch or bedding material for livestock
PAG~
PREVIOWS BLANK
9
Introduction: Erosion and runofffrom
deforestation, overgrazing, fires, and poor Collecting and preparing
agronomic practices threaten the vetiver slips for planting:
environment and agricultural production.
1. Collect planting material afterthe
Planting perennial bunch grasseson the
rains start, and plantwithin 48 hours.
contour provides agood barrieragainst
2. Selecthealthy, well established clumps
erosion and runoff. With properspacing
of grass.
and management, natural terraces form
between the contour hedges as soil 3. Trim the grass to 30 cm tall before
moves from the upperside to the lower digging up (Fig. 5).
side behind the hedge. Contourhedges
4. Makevertical cuts to dig out clumps
also slow down and retain waterthat
with roots; leave 15%ofeach clump
would otherwise be lostthrough surface
for nursery regeneration (Fig. 6).
run-off. Multi-purposetrees or shrubs
may be planted above the grass hedges. 5. Keep clumps upright in shade and
awayfrom wind to reduce drying out
NOTE: Grass hedges are used to reduce until planted. Waterthe collected
runoffand erosion, NOTto stabilise planting material if itbegins to dry
marker ridges which are simply guides to out.
re-align ridges on contour.
6. On the dayofplanting, trim leaves of
collected clumps to 15 cm to reduce
The Grass: Vetiver is afast growing,
transpiration and to encourage
deep-rooted perennial grass well adapted tillering; then dividethem intoslips
to all agro-ecological zones in Malawi. It each with 3-4 tillers and 5-10 cm of
is notcompetitive with crops and is not
roots (Fig. 7). The slips are nowready
known to host pests and diseases of
for planting in nurseries oralong
concern to agriculture. Vetiver seed has
contour lines to establish dense
lowviability, so there is littlechance ofit hedges. Use largerslips with 5-10
becoming aweed. It is easyto establish tillersfor planting inside gullies.
and maintain, and itmakesgood
thatching, mulch, and bedding material
for livestock. Vetiveria zizanioides is the
preferred species because itgrows faster
and forms adenserand more leafy hedge
than Vetiveria nigritana.