OR H EO / A 3 8 / 2
M a c k , H. J .
p4 T 22
s!=il9:-!
E f f e c t of row sp ac i n g s on
p r o c e s s i n g c a r r o t root
NOT
FOR
LOAN
Oregon
9 U j \ j
4
1980
state
ubrary
HortScience 15(2): 144—145. 1980.
Effect of Row Spacings on Processing
Carrot Root Yields1
H. J. Mack
Department o f Horticulture, Oregon State University, Corvallis,
OR 97331
Additional index words, plant populations, seeding rates, Daucus carota
Abstract. Total root yields as well as roots <25 and 25-38 mm diameter, were increased in
carrot (Daucus carota cv Red Cored Chantenay), as row spacings were decreased from 60 to
15 cm in 2 field experiments. Different within-row seeding rates did not have a significant
impact on total yields, but affected yields o f various size grades.
Most U.S. carrot processors accept
a range of root sizes from about 20 to
65 mm in diameter, but the range of
acceptable sizes for fresh market sale is
not as great. Webster (15) determined
' that maximum yields of salable roots
were obtained from carrots spaced 4
to 6 cm apart in 30 cm rows (55-83
plants/m2). Warne (12, 13) found that
yield of roots was highest in 45 cm rows
at 2.5 cm within-row spacing (89
plants/m2). When 30. cm rows were
used, Warne (14) showed a total yield
increase of. 48% as populations were
increased from 60 to 305 plants/m2.
Robinson (9) obtained highest root
yields at a square grid spacing of 5.1 x
5.1 cm-(384 plants/m2); densities of
1359, 5439, and 22,305 plants/m2
. produced greater dry matter yields,
but the roots did not reach marketable
size in 150 days. The lowest yield of
dry matter was at 10 cm square grid
but this spacing produced the earliest
roots of marketable size. Kepka et al.
(7) reported the largest increase in
carrot yield when plant density in­
creased from 37 to 167 plants/m2.
Bleasdale (2) showed that root size can
be controlled by varying inter- and
intra-row spacings. Highest yields of
19-32 mm diameter roots were pro­
duced in 9 to 13 cm rows at popula-
1 Received for p u b lication May 29, 1979.
Oregon A gricultural E x p erim en t S tatio n T ech­
nical Paper No. 5193,.
The cost o f publishing this p ap er was d e ­
frayed in p art by th e p ay m en t o f page charges.
U nder postal reg u lations, th is paper m ust
th erefo re be hereby m ark ed advertisem ent
solely to indicate this fact.
144
tions of about 400 to 500 plants/m2.
Bussell (6) produced small finger
carrots (roots 13 to 18 mm diameter,
7.5 to 11.5 cm long) using row spacings
of 2.5 to 7.5 cm, and he showed that
yield increased as the sowing density
was increased from 533 to 2500 seeds/
m2. "
The present study was conducted to
determine the effect of row spacings on.
yield of various size grades of roots of
‘Red Cored Chantenay’, a processing
cultivar. Two field experiments were
conducted in separate years on a loam
soil at the Oregon State University Vege­
table Research Farm, Corvallis. Row
spacings of 15, 30, 45, and 60 cm were
used. Broadcast fertilizer rates of 56 kg
N, 74 kg P, 47 kg K/ha and 112 kg N,
148 kg P, 94 kg K/ha were used in
Experiment 1, but only the former
rate was used in Experiment 2. The
fertilizer treatments in Experiment 1
did not have a significant effect on
yield, and the yields reported for this
experiment are averages of the 2 treat­
ments. Plots were irrigated by overhead
sprinklers at 12 to 20 day intervals.
Roots were harvested from the center
row of multi-row plots' and at least
2 border rows remained on each side
of the test row for the 15 cm row
treatment and at least 1 border row
remained on each side of the test row
for the 30, 45,. and 60 cm row treat­
ments. Roots were separated into the
following size grades (mm shoulder
diameter): <25, 25-38, 39-51, 52-64,
and >64 mm. In Experiment 1 plots
were planted with a Planet Jr. hand
seeder (plate hole 6) on May 19. Early
stand counts were not made, but root
counts made about 10 days before
harvest indicated the following average
populations/m2 for each of the 4
row spacings: 15 cm, 238; 30 cm,
129; 45 cm ,.86; and 60 cm, 76. Treat­
ments were replicated 3 times. Plots
were harvested on October 4. In Experi­
ment 2, 3 seeding rates (low, medium,
and high) were used at each of the 4
row spacings. Planting was on May 25
and harvest was on September 27-28.
The 3 seeding rates were accomplished
by using Planet Jr. plant holes 6, 9,
and 12. Treatments were replicated 3
times. Average number of roots/m2
before harvest for the low, medium,
and high seeding rates were as follows
for the 4 row spacings: 15 cm — 212,
316, 534; 30 cm - 107, 209, 323;
45 cm — 82, 163, 262; and 60 cm —
72,129,221.
Decreasing the row spacing from the
conventional 60 cm to 15 cm increased
total yields 32 and 27% respectively,
in Experiments 1 and 2 (Table 1 and
Fig. 1), and also increased yields of
smaller sized roots, <25 and 25-38
mm in diameter. Highest yield of larger
sized roots, 52-64 mm, was produced
at 60 cm row spacing. No significant
effect of row spacings on yield of 39-51
mm diameter roots was found in either
experiment. Main effects of within-row
seeding rates in Experiment 2 indicate
that total yields were found not to be
significantly different at the 3 seeding
rates, but yields of various sizes ofroots
were affected. The high seeding rate
produced higher yields of small roots
and lower yields of large roots than the
low seeding rate. The individual effects
of the 4 row spacings and 3 seeding
rates on yields of various size grades
of roots are shown in Fig. 1. No signifi­
cant row spacing x seeding rate, interac­
tions were found.
Population density at harvest on an
area basis (about 210 to 220 roots/m2)
in Experiment 2 was similar for 60 cm
rows at the high seeding rate, 20 cm
rows at the medium seeding rate and 15
cm rows at the low seeding rate and the
respective total yields were 73.1, 81.9,
and 95.1 MT/ha. This 30% increase in
total yield indicates that an arrangement
in which plants are more evenly dis­
tributed in a given area is advantageous.
The major yield increase of the 15 cm
rows with a low seeding rate over the 60
cm rows with a high seeding rate was in
the production of 113% higher yield
of 39-51 mm diameter roots (Fig. 1).
Ho r t Sc i e n c e , Vou. 15(2), Apri l 1980
Table 1. Effects of row spacings on yields of carrots, Expt. 1.
__________ Yield (M T/ha)_________________________ R o w spacing
(cm )
< 25 mm
15
30
45
60
10.5
3.4
1.6
1.1
47.1
22.9
15.3
10.3
2.1
2.9
4.4
6.1
LSD 5%
• 1%
Size d istrib u tio n o f ro o ts
25-38 m m
.39-51 m m
52-64 m m
38.7
36.4
32.8
28.7
NS
NS
> 64 mm
T o ta l
yield
10.8
27.4
28.0
30.2
2.7
9.9
13.2
12.7
109.8
100.0
90.8
83.0
5.8
8.1
5.1
7.2
10.5
14.7
NSNon sjgm fiCant.
grades, and harvest efficiency could
also be influenced by hybrids, planting
and harvest dates, and other factors
(1 ,3 ,5 , 8,9, 10).
- Literature Cited
1. Ilienz, D. R. 1965. C arro t sp littin g and
second grow th in central W ashington as
influenced by spacing, tim e o f sidedressing and o th er cultural practices. Proc.
A m er. Soc. H ort. Sci.
8 6 :4 0 6 -4 1 0 .
2. Bleasdale, J. K, A. 1963. The bed system
o f carro t growing. U.K. M inistry o f Agr.,
Fisheries & F ood. S h o rt T erm L eaflet
2 7.
3.
Fig. 1. E ffects of 4 row spacings and 3 seeding rates on yields o f various sizes o f carrot ro o ts,
E x p t. 2.
These results are in agreement with
Bleasdale (2, 3, 4) who suggested that
yields are higher when plants are more
evenly distributed. They are in con­
flict with results of Bussell (6) where
row- spacings were quite narrow, ranging
from 2.5 to 7.5 cm and plant densities
were high, 533 to 2500 seeds/m2.
Bussell used different cultivars with the
objective to produce small, finger
carrots.
Although our results show that
higher total yields and higher yields
of smaller roots of a specified size
grade can be achieved through reducing
the row spacing from the conventional
60 cm, present harvest systems .may
limit the application of this knowledge.
Most of the lifter type carrot harvesters
require a row spacing of 25-35 cm or
more. It may be feasible to use a series
of double or triple rows spaced at 4
to 6 cm, or a wide-band seeding pattern
(7), with a spacing between these rows
of 40 to 45 cm to accommodate lifter
harvesters, but these spacing arrange­
ments were not investigated. In the bed
system of carrot growing described by
Bleasdale (2), 2-row potato harvesters
can be modified to harvest carrots after
tops have been removed in a separate
operation, thus narrow row .plantings
are feasible. However, Tucker (11)
reported that top-lifting harvesters were
less damaging to roots than diggerelevator type harvesters. Yields, size
HORTSCIENCE, VOL. 15(2), APRIL 1980
• -•______ _ 1963. Crop spacing and
m anagem ent u n d er w eed-free co n d itio n s.
5>ymp.r British . Weed C o n t. C ouncil.
3, p. 90-101. Blackwell S cientif. Publ.,
O xford.
4 . ____________ _ 1966. Plant grow th and
crop yield. A n n . A p p l. B iol. 5 7 :1 7 3 -1 8 2 .
5 . ____________ _ 1973. C o n tro l o f size
and yield in relation to harvest date o f
carro t ro o ts. A c ta H ort. 2 7 :1 3 4 -1 4 3 .
6. Bussell, W. T . 1973. E ffect o f plant
density and tim e o f harvest on yield o f
sm all finger carrots. N .Z .J. E x p t. Agr.
1:69-72.
7. K epka, A ., L. U m iecka, and H. F ajkow ska. 1978. The influence o f row spacing
and plant density in row s on the yield o f
carrots and ro o t q u ality . A c ta H ort. 72:
217-224.
8. M ann, L. K. and J. H. M acGillivray.
1949. Som e factors affecting th e size of
carro t ro o ts. Proc. A m er. Soc. H o rt. Sci.
5 4 :3 1 1 -3 1 8 .
9. R obinson, F. E. 1969. C arrot p o p u latio n
d en sity and yield in an arid en v iro n ­
m ent. A gron. J. 61:499-5 0 0 .
10. T h om pson, R. 1969. Som e facto rs
affecting carrot ro o t shape a n d - size.
E u p h ytic a 18:277-285.
11. T ucker, W. G. 1974. The effect o f m e­
chanical harvesting on carro t qu ality and
storage p erform ance. A cta Hort. 3 8:359372.
12. W arne, L. G. G. 1951. Spacing ex p eri­
m ents on vegetables. I. The effect o f
thinning distance on earliness o f globe
beet and carrots in C heshire, 1948. J.
H ort. Sci. 26:79-83.
1 3 . ______________ . 1951. Spacing ex p eri­
m ents on vegetables. II. The effe ct o f
thinning distance on th e yields o f globe
b eet, long beet, carrots and parsnips
grow n at a standard inter-row distance
in Cheshire, 1948. J. H ort. S ci.' 2 6 :8 4 87.
14. _____________ . 19S3. Spacing ex p eri­
m ents on vegetables.. VII. The grow th and
yield o f globe beet, parsnips, and carro ts
grown at several spacings in two ad jacent
fields o f different fertility . J. H ort. Sci.
2 8 :114-120.
15. W ebster, A. B. 1969. M anuring and
spacing experim ents on vegetables. N .Z .J.
Agr. R es. 12:381-416.
145