If only I knew
then...
Here are some of the questions that we wish
we'd had answers to earlier. Some of them are
things we've learned by trial and error, others
are bits of information that we found after
it was too late. Not all of them are things
that have gone wrong, but all of them would
have added to our ability to make a considered
decision.
We are constantly adding information to this
page, so if we have hinted at something but
it isn't clear, or if there's just a short note
to remind us to go back and fill in the detail,
please remind us...
Dieback - what's wrong with
my hazelnuts (late spring/summer)
Grass - what's causing the
dead patches?
Orchard management -
what are the understorey options?
Orchard management - should
I spray out between my trees to give clear rows?
Grass - do I need to replace
the pasture grass with slow-growing turf?
Irrigation - microspray
or dripper?
Irrigation - when
is the best time to irrigate?
Irrigation - how do
I know when I need to irrigate? How much? How
long for? How often?
Mowing - contractor, tractor,
ride-on or farm-bike plus attachment?
Shelter requirements
- what sort of shelter do I need?
Spacings between trees -
what do I need to consider
Pruning
Nutrients
Cultivars
Will hazelnuts sucker throughout their lifetime
or will they give up after a few years?
Dieback - what's wrong
with my hazelnuts (late spring/summer)
After planting trees in July 2005, they seemed
to be taking ok and putting out some nice
new growth. A couple of months into spring,
about 25% of them started to show some browning
off of the leaves, and for most of these the
branches started to die back.
A more common problem that we have is in
early spring. The trees form buds over winter,
but these just fail to develop in spring and
the tree has to regenerate from a sucker.
This means that you lose the previous year's
growth completely and are starting over again
each year for the first three or four years.
It seems to be less of an issue after this.
We have conflicting information about this:
- (Nov 2005, own theory) It only seems to
affect the trees just planted, and then only
the Whitehearts but not the pollinators. Could
their root systems be too weak to support
all the new growth?
- (Nov 2005, consultant SB) Probably blight,
could be controlled by a copper spray if caught
early.
- (Jan 2006, internet) Dieback can be caused
by boron deficiency (which we think we have).
- (Feb 2006, consultant SB) Almost certainly
blight. The nursery has admitted that they
had a bad outbreak and they probably never
got it quite under control. Although they
supplied the healthiest trees they had available,
they were still in poor condition and the
planting stress may have made them more susceptible
to illness.
- February 2008 (nurseryman and researcher
MR) Probably not blight. Could be that the
roots don't have enough resources to sustain
the tree. The stem has enough energy for the
first year when it goes in but when this is
exhausted, if the roots can't supply enough
then the tree fails. This seems to affect
quite a few recent plantings, especially where
the trees go in at a very small size (as ours
have). It didn't used to be an issue because
historically trees went in slightly older
(after a couple more years growing on in the
nursery).
Grass - what's causing
the dead patches?
In summer we ended up with significant die-off
of our grass, in large patches. Traffic areas
(accessways) were least affected. At first
we thought it was spray drift, but now we
believe it is porina larvae, which burrow
into the soil to develop and eat the grass
off at ground level. It came back ok the next
spring, but it was pretty distressing at the
time.
No organic remedy we're aware of, the recommended
action is an application of organophosphate
in autumn. Opinion is divided as to whether
you are likely to get annual reinfestations
or whether it is random.
Orchard management
regimes - what are the options for my understorey?
Understorey management is only an issue until
the trees are big enough to achieve canopy
closure and full shading of the ground (at
this point, the tree roots will take all the
water and not much will survive in the permanent
full shade).
The most common understorey in establishing
orchards in New Zealand is grass (see below),
although other options are also available.
These include:
- a herbal ley. Our vague understanding is
that this is a variety of grasses and weeds,
which pull various nutrients out of the soil
and allow you to mulch this back onto the
plants. Natural fertiliser. It's a nice idea,
but we haven't seen enough literature to evaluate
this.
- cash crop such as lucerne or barley. Also
a nice idea, but it means you can't use the
space between the rows for traffic or to manage
your trees. This might work quite well if
you don't want to use any control mechanisms
around the trees (or can get to everything
on foot).
- bare earth. You could spray out all grass
etc, although this could lead to topsoil loss
and is also not a great way to retain moisture
in the soil.
Orchard management
regimes - should I spray clear rows between
my trees?
The options available are to spray small
patches around each tree, to spray rows, or
not to spray at all.
If you are philosophically opposed to herbicides,
the answer is probably no. It is not strictly
necessary, but the trees will establish much
better if they are not constantly competing
with weeds and grasses so you should find
a way to manage these (a dessicant spray could
be used instead of Roundup etc).
Clear rows are easier to maintain than spray
circles. Your spray tank can be mounted on
a vehicle and you can go up and down each
side of the row and do all your spraying quite
quickly and easily. If you have grass between
the rows, you can mow and mulch this onto
the sprayed strips to retain soil moisture
and return organic matter.
Spray circles can be maintained as a two
person job, one to move the vehicle from tree
to tree and the other on foot to take the
hose and spray around (or one person could
do it, hopping on and off). A 15 litre
knapsack sprayer won't take you far! Mowing
is also more difficult, you need to either
do a criss-cross pattern or else figures of
eight; neither of these is highly efficient.
Grass - which is better,
pasture grass or slow-growing lawn turf?
This is a particularly tricky issue, as the
answer depends on your priorities. (The size
of your property is also relevant.) Fescue is
probably not a feasible option for an organic
orchard.
| Pasture grass |
Turf grass (fescue) |
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Advantages
- Cheaper to set up - it's usually
there already.
- Survives ok without too much irrigation
(so less cost from pumping water
etc).
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Advantages
- Looks good - gives a smooth, even,
bowling-green finish.
- Lower maintenance - it grows slower,
so needs cutting less often.
- This is the point that is
most often used to sell the
idea as a practical advantage
but please note that depending
on your irrigation layout, it
may not be any slower than pasture
grass after all. If you are
using a broadcast irrigation
method, such as spray jets or
microemitters, you will be irrigating
the grass just as much as the
trees. This makes it look lovely
and green, but our experience
is that you need to cut the
grass at least every three weeks
to keep it under control, which
is the same sort of frequency
as pasture grass.
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Disadvantages
- Grows fast so requires frequent
mowing or other control (after all,
its main purpose is to generate
enough green matter to sustain stock).
- May grow unevenly so it doesn't
always look particularly great.
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Disadvantages
- Higher set-up cost because you
generally need to cultivate the
soil and sow new seed.
- We strongly recommend that
you spray out the old grass
thoroughly first, probably a
couple of months beforehand
so you can do a second spray
when it starts to regerminate
and then still have time to
plough it under to break down
before you re-sow.
- Higher set-up cost if you want
to achieve the lush, green, bowling
green finish because you will have
to irrigate the grass as well as
the trees. This means large pipes
and more work laying it.
- Maintenance costs because you
may have to spray out aggressive
weeds, which will almost always
be more vigorous than fescue.
- Harder to mow. Fescue has lots
of very fine (and strong) blades
of grass. To cut it successfully,
you need to keep your mower blades
really sharp. On good soil with
good moisture, you will still need
to mow it at least every three weeks
(and preferably every two weeks)
to keep it under control. Any longer
than that and you will put unnecessary
strain on your equipment.
- We were told that this should
only be the case for the second
and possibly third years because
this is when the grass puts
on most of its growth for establishment,
and it slows down after that
(in the first year it is still
sparse because it is establishing).
We haven't seen any evidence
of this so far.
- For it to look nice with a bowling
green finish, you need to have a
very good weed control regime. Ideally,
make sure none come up in the first
place (hence the spraying out before
sowing)
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Irrigation - microspray
or dripper?
Dripper is more water efficient, which can
save money in many ways, including:
- shallower bore
- smaller pipework
- less hassle getting a consent (maybe)
- less time irrigating (maybe) = less electricity
(only if the first holds)
To get enough water to the trees, you probably
need to install a run of dripper tube down
each side of the tree row. Leave enough slack
that you could eventually move these outwards
as the trees grow and their roots move out.
Be aware that if you have dripper tube above
ground, it will shrink in the sunshine so
the rows will shorten (or if you have circuits,
the joins will come under pressure and may
pull apart).
Microsprayers are required if you have lawn
turf and you want to keep it green in summer
(otherwise it browns off completely, but should
come back in winter). This pretty much defeats
the real attraction of turf, which is the
low maintenance - we are mowing ours every
other week.
Microsprayers mean the trees' leaves are
wetted, which could increase the risk of fungal
diseases - but this has not been conclusively
proven.
The stakes that the sprayers are on tend
to get pushed out of the ground over winter
as the soil contracts with frosts, so you
may have to go around in early summer to make
sure they are all correctly in place. Also,
the tube connecting the spray head to the
lateral may work loose so you will periodically
need to check that as well.
What did we do? We have microsprayers
covering essentially the entire block. Doing
it again, we would probably use dripper tube.
Irrigation
- when is the best time to irrigate?
Water soaks in better at night.
Daytime irrigation could burn the leaves.
Night time irrigation could increase the
risk of fungal disease.
Irrigation
- how do I know when I need to irrigate? How
much? How long for? How often?
As well as the weather, this depends on your
soil and how well it retains the water.
Mowing - contractor,
tractor, ride-on or farm-bike plus attachment?
The economics of this question very much
depend on the size of your property.
Contractors are convenient and a known
cost, but very expensive on a large scale.
On the other hand, you don't need to worry
about maintenance, insurance, running costs
and equipment storage. They are more skilled
than a novice at handling the equipment and
working efficiently, but then again they aren't
emotionally involved so will almost certainly
take less care than you. If you are strongly
in favour of side discharge in order to mulch
the rows, you will need to check whether the
individual contractor's equipment supports
this.
The commonly available ride-on mowers
are designed for properties smaller than 10
acres. If you are larger than this, you will
need to think about a grunty commercial model.
Commercial models are designed to survive
in a contracting or professional situation,
so up to 8 hours a day, 40 hours a week. Petrol
models start from around $20,000, and high-end
diesel models are around $45,000 (including
gst). Basically, you work out your budget
then take the largest model that fits. We
believe that the working life of a commercial
ride-on in heavy use is around 10-15 years,
if well maintained. The up-front cost probably
works out about the same as using a contractor
for 5 years. Running costs are on top of this,
but on the other hand if the mower lasts longer
then you are starting to win. Some of the
leading suppliers have recently brought out
large ride-ons in a 'heavy residential' grade
(so slightly less rugged than the commercial
mowers - presumably they were finding that
people were scared off by the price tag).
The life of these is more likely 5-10 years
and there is more chance of a breakdown. If
you want your equipment to definitely be working
when you want to use it, there is more risk
involved with these.
The cost of tractors depends on age,
brand and size. It is quite common to purchase
second hand tractors, but do try before you
buy - some are much more comfortable and easy
to handle than others. For size, think about
what you will want to use it for in the long
term and buy the size you will eventually
need. The cost of a tractor plus mower unit
is probably around the same as a large ride-on
(and tractors cover the full range of prices
too), but will last longer and should have
lower running costs. As regards our Jinma,
the tractor seems pretty sturdy but we're
less certain about the mower unit. We have
replaced three pulleys, gone through three
sets of blades and replaced umpteen drive
belts. Because it's a small brand there is
no established support agent (the sales guy
isn't geared to lifestylers), so it is hard
to find parts. If you have a Jinma and have
had problems, email us because we're happy
to share what we've learnt!
Tractor mowers are driven by the PTO and
most are pulled behind the tractor, which
makes them difficult to manoeuver around planted
blocks. Mid-mounted mowers are easy to manoeuver
but hard to get at for maintenance.
Mower attachments for farm bikes can be fairly
expensive, but are reputed to be longer lasting
and more powerful than similar size ride-ons,
simply because the mower unit has its own
motor.
What did we do? We started out with
a tractor and mid-mount mower. The tractor
is great, the mower has been a constant source
of frustration because it is always falling
apart. After 3 seasons (so it has paid itself
back compared with contractor), we are buying
a top-of-the-line zero turn ride-on. 25 HP
petrol motor, 60" side discharge.
The ride-on is about three times faster than
the tractor, so each block will take about
15 minutes to cut instead of 45-60. The ride-on
doesn't heat up as much as the tractor either
- we had to stop for 30 minutes every 2 1/2
hours to let the tractor cool enough to not
boil. This appears not to be an issue with
the ride-on (maybe it is petrol vs diesel
engine, or maybe just the design of the cooling
system).
Another disadvantage of the tractor mower
that we had was that it was hard to get on
and off the tractor (actually, our from underneath).
This meant that we had a dedicated mower but
couldn't easily use the tractor for other
equipment (eg sprayer, spreader, grader, post
hold borer...), which is one of the big advantages
of a tractor in general.
Shelter - what sort
of shelter do I need?
The exact requirements for shelter depend
on your site and its local environment, but
basically you need enough shelter to protect
the trees from harsh winds while they are
establishing. If you don't have adequate shelter,
it will slow your establishment significantly
- by up to 5 years we think. If you are in
Canterbury, where you can get several days
of very strong winds at a time, you shouldn't
even think of planting crop trees until your
shelter is fully established.
On this count, we are the voice of sad experience.
We were advised that walnuts would need shelter
to be established for several years ahead
of planting but hazelnuts should be ok planted
concurrently, and we have found that our trees
have suffered badly from this. The trees planted
later, when the shelter is higher, have established
much better than the trees planted earlier,
with almost no protection.
Without adequate shelter, your trees may
survive but are unlikely to thrive.
For more information on designing shelter
and selecting shelter species, talk to your
local nursery - in Canterbury, Southern
Woods are very helpful.
What did we do? Our southern shelter
(coldest winds) is leyland cypress. They took
about 3 years to settle in but started to
grow faster after that. When we were planning
our layout we intended to plant hazelnuts
on the western half and walnuts on the eastern
half, and so we have two different types of
shelter to accommodate this. For the walnuts,
all the shelter is crowsnest poplars - tall,
fast growing, deciduous so they don't provide
too much shade (and frost traps) in winter.
In the east, we have two schemes. For the
nor'west wind (very strong) we have Italian
alders alternating with poplars. For the nor'easter
(not as strong, but much more frequent) we
have Italian alders alternating with native
NZ shrub species. The poplars are doing really
well (also took a couple of years to get started
but shot off after that) but the alders have
been less successful (more fatalities for
no known reason, but we suspect they need
more water than we thought). Starting again,
we would recommend allowing the shelter to
grow for at least three years before putting
in any crop trees.
Spacings between
trees - what do I need to consider?
The space you need between trees depends
on several different factors. The most important
consideration is the size that the tree will
grow. You need to have enough space between
the trees that they can grow to full size
comfortably and the edges of adjacent trees
will just touch when they are mature (full
canopy cover).
Most trees provide a better crop when they
get plenty of sunlight on their branches and
leaves, so make sure there is enough room
for this.
The most efficient use of land area is to
plant trees in an offset grid/diamond pattern.
This means that you might plant a row of trees
for example three metres apart. You could
plant the next row three metres over, but
instead of lining the trees up with each other
in a square grid pattern, you could plant
them so that the rows were staggered - the
trees in the second row would be halfway between
the trees in the first row; the trees in the
first and third rows would line up. This gives
the maximum canopy space per tree. Despite
the mathematical elegance of this design,
we haven't heard of anyone actually using
it.
More commonly, trees are planted in rows.
Within the rows the trees are fairly close
together but the space between the rows is
larger. This allows you to strip-spray herbicide
around the trees to reduce competition from
weeds and grasses while they are establishing,
and also allows enough room for large equipment
to work in your orchard. As well as mowing,
don't forget that you may need room for a
large tractor to spray fungicide or foliar
fertiliser on your trees, or you may need
room for a truck to spread granular fertiliser
on the ground.
As well as space between the trees in the
orchard, you also need to decide how much
room you want to leave at the end of each
row and at the sides of the block. This 'headland'
and 'sideland' space give room to turn equipment
at the end of the row. Five metres is the
minimum you should consider and we would suggest
that you actually leave more than this (and
when we say five metres we mean actual space,
not distance between the centre of the shelter
tree and the centre of the crop tree). This
gives you much more flexibility when considering
maintenance options. On the other hand, that
is valuable space that you are not cropping
- how much would you earn by having trees
in that space and how much do the different
maintenance options cost you?
What did we do? Whiteheart hazelnuts
are fairly small so ours are planted in rows,
2.2 m apart in the row and 4.5 m
between the rows. Our headlands and sidelands
are 5 m. In practice, this works well
for routine management - we have sprayed the
rows out to 0.75 m each side of the trees
so we have a mowing strip of 3 m which
we cover in two passes. However, it is hard
to find a contractor to spread bulk granular
fertiliser because the headlands are too small
for them to turn a large spreading truck.
While the trees are small, 2.2 m looks
like plenty of space between them. However,
when they get a bit bigger this may be a little
too close. Starting again, we would probably
allow 2.5 m between the trees so that
we could train them into a more conventional
open vase shape. As it is, we will probably
have to use something more like a flattened
cone. We would also allow more space at the
headlands, more like 5.5 m of clear space
(between the end of the sprayed hazel strip
and the edge of the shelter sprayed strip).
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