Natural Resources, 2011, 2, 234-239
doi:10.4236/nr.2011.24029 Published Online December 2011 (http://www.SciRP.org/journal/nr)
An Initial Investigation on the Distribution, Living
Conditions and Traits of the Hazel in Great
Xing’an Ridge Region
Qian Wang1#, Shuchai Su1*, Wanping Liu1, Dejie Yin1, Zhongqiu Tang2, Di Xu2
1Key Laboratory for Silviculture and Conservation, Ministry of Education, Beijing Forestry University, Beijing, China; 2Agricultural
and Forestry Research Institute of Great Xing’an Ridge, Jiagedaqi, China.
Received August 6th, 2011; revised August 20th, 2011; accepted Septe mber 5 th, 2011.
ABSTRACT
To take full advantage of the natural hazel resources and improve its yield and quality in Great Xing’an Ridge region, we
carried out an initial investigation. The result showed that: there are two species in this area: Corylus heterophlla and
Corylus mandshurica. They mainly distribute from south of Xinlin town, Huma county, Heilongjiang province to south
boundary of Great Xing’an Ridge in mountain and hilly areas. Most of hazel in this area was under the state of natural
growth with no scientif ic man-mana gement. Soil where Corylu s heterophlla grew wa s about 40 cm to 50 cm an d Corylus
mandshurica was 30 cm to 45 cm. The main plant disease was powdery mildew and insect pest were Curculio dieckmani,
Zeuzera sp. and Faust Cockchaf er. 100-seed weight of C oryl us hete roph yl l a was more t ha n t w ice of Corylus ma nds h uri a.
However, Corylus mandshuria was plumper, had much more kernel an d mu ch less emp ty shell tha n Co rylus h etero phylla,
and what’s more, shell sickness of it turned to be significantly thinner than Corylus heterophylla, all of which showed
great cultivation value and economic commodity value.
Keywords: Corylus Heterophylla, Corylus Mandshurica, Distribution, Quality, Condition
1. Introduction
Hazel which originated in China and rich in fat, protein,
carbohydrates, tog ether with many kinds of vitamins and
minerals is a kind of precious woody grain and oil re-
sources, containing a high economic value. According to
the analysis, hazel contains 57.5% - 69.8% fat, 14.1% -
18.0% protein, 6.5% - 9.3% carbohydrate, only 4.1% -
5.8% water and a variety of vitamins (Vc, Ve, Vb) and
minerals (Ca, K, P, Fe etc.) [1]. What is more, unsatu-
rated fatty acid content reaches up to 90% in hazel oil,
far higher than conventional vegetable oils. Among the
oil oleic acid is the most (74.1% - 82.1%) and linoleum
acid come to the second (12.7%). It contains much less
iodine and is clear orang e with mellow taste, so turns out
to be a high quality oil [2]. Hazel is one of the world’s
four nuts and is well received by consumers due to its
rich nutritious and unique flavor. Hazelnut oil can soften
blood vessel, which could help the elderly prevent car-
diovascular disease and promote longevity [3]. Distribu-
tion of hazel root is deep and wide, which could reach
1.5 m deep and 1 - 2 m wide respectively. Meanwhile,
they are easy to form continuous hazel forest because
their roots could stretch in the surface soil and sprout
tillers [4]. As a result, it becomes very helpful for soil,
water conservation and for woodland soil improvement
due to its well-developed root system.
Hazel belongs to Cory la c ea e, Corylus L. in plant tax-
onomy and there are about 20 species around the world.
They mainly distribute in the Northern Hemisphere from
Cold Temperature Zone to Subtropical Climate Zone [5].
10 of the 20 species originated in China and scattered in
22 provinces (regions), among which Corylus hetero-
phlla, C. mandshurica, C. kweichowensis Hu, C. chinen-
sis Franch, C. fargesii Schneid, C. yunnanensis A. Ca-
mus, C. ferox Wall, C. wangii Hu were 8 original species
#Wang Qian, Master in Beijing Forestry University.
East Road, Beijing 100083, China.
*Corresponding Author Introduction: Su Shuchai, professor. Research:
Pomology.
East Road, Beijing Forestry University.
This study was supported by State Forestry Administration Key Project
“Study on key technology about Hazelnut Breeding and Cultivation”
(2011-03).

An Initial Investigation on the Distribution, Living Conditions and Traits of the Hazel in Great Xing’an Ridge Region235
and Corylus heterophlla × corylus avellana and C. avel-
lana L. are 2 cultivars [6].
Corylus heteroph lla and Corylus mandshurica are two
species containing high economic value in the north of
China. Corylus heterophlla, a small deciduous tree or
shrub and alias hazel or hazelnut, mainly distribute in
mountains or hilly regions at an altitude of 200 - 800 m.
It is divided into 7 types according to different shapes,
and they respectively are round hazel, cone hazel, oblate
hazel, long round hazel, flat hazel, sharp hazel and flat-
topped hazel [7]. Corylus mandshuria, alias fire hazel or
Corylus mandshuria maxim, is a 2 - 4 m tall shrub. They
distribute in forest or mountains in Temperate Zone or
Warm Temperate Zone, and often grow among birch,
aspen, Mongolian oak, oak or on the edge of other sum-
mer green broad-leaved forest.
Hazel is a major nut tree in China. It distributes in
Heilongjiang, Jilin, Liaoning, Inner Mongolia, Hebei,
Shaanxi and Shanxi provin ce. In China, this ancient fruit
tree is always in the original wild state and research on it
has not begun until the 1 970s. After thirty years research,
hazelnut was finally included within cultivation fruit tree.
Consequently, Hazel, the new fruit tree who has long
been known but with so short h istory of artificial cultiv a-
tion has attracted more and more attention with the im-
plementation of the conv ersion of cropland to forest pro-
gram and development of economic forest industry [8].
Nowadays, the current development and utilization
and other aspects of the research of hazel focused on the
biology and ecology in China from the economic forest’s
development status. As oleiferous tree species, hazelnut
could bring tremendous economic and ecological bene-
fits through scientific management, and meanwhile pro-
mote local economic development together with people’s
income increase.
Because hazel has always been in the original wild
state in China, it led to smaller nuts, low kernel rate and
poor commodity traits. What’s more, serious insect fruit
result in yield and quality significantly decreased. In re-
cent years, not only no hazel was exported from China,
but a large number of large fruit-European hazelnut was
imported as hazelnut decline in the quality in China,
which has a serious impact on our hazel industry [9]. In
summary, detailed investigation and scientific manage-
ment on wild hazel resource in China is imminent.
Most of hazel in Great Xing’an Ridge region is simi-
larly under pure wild growth at this stage with no scien-
tific artificial management. In addition, development of
hazel product in this area is still in primitive stage and
the major sales are primary original products. Given the
status of local hazelnut resources, we conducted this pre-
liminary investigation and study in order to make full use
of this wild hazel, to improve its yield and quality. And
the last purpose of the present study is to provide a theo-
retical basis for rational exploitation and utilization .
2. Materials and Methods
2.1. Sampling Site and Background
Great Xing’an Ridge is an important mountain in the
northeast of China and it stretches from 43˚ - 53˚30'N
latitude to 117˚20' - 126˚E longitude. Altitude of moun-
tains range from 600 - 1000 meters, and some peaks are
close to 1400 meters. This area has large temperature di-
fference between day and night. The annual average
temperature is –1.2˚C - 5˚C, and the lowest temperature
is –52.3˚C. July average temperatures is 16˚C - 20˚C.
The annual accumulated temperature reaches 1100˚C -
1700˚C. Its frost-free period is about 90 - 110 days, and
average annual precipitation achieves 400 - 600 mm.
What is more, Great Xing’an Ridge is covered with vast
expanse of forest. Its forest area is 6,463,600 hectares,
and forest coverage rate reaches up to 75.16%.
Great Xing’an Ridge in northeast of China own the
richest hazel resource. The area of hazel in Great Xing’
an Ridge came up to 670,000 hm2 [10]. They mainly
distribute in sunny, fertile, deep, well drained mountain
soil in southeast of Great Xing’an Ridge. The hazel here
is often contiguous and focused and large hazel forest
range from one hectare to hundreds hectare. Hazel shrubs
can be divided into shrub layer and herb layer, and the
cover degree of shrub layer could come up to 78% - 80%
which composed mainly by hazel with 80 000 - 150,000
hazel trees per hectare in average [11]. Although there
were so much hazel resource in Great Xing’an Ridge,
they had always been in the state of natural wild growth
and had never really got exploration.
For a long time, production structure of forest area
was single and exploration, utilization and protection of
hazel had not been paid enough attention. Consequently,
greens nuts were always picked by local people in every
harvest reason with deforestation, thus, resulting in nut
yield and quality declining and increasing proportion of
empty seeds, shriveled kernels and serious insect nuts.
So, we randomly chose several sampling sites for sur-
vey orderly from Jiagedaqi County, Nenjiang County
and Huma County to make an initial investigation and
research to provide a theoretical basis for rational exploi-
tation and utilization.
The following considerations were used to select sam-
pling sites: 1) the area should be wide and easily identi-
fiable in GIS images, and 2) the area should not be de-
stroyed by farmland or highways and could represent the
local hazel growth conditions. Therefore, based on the
aforementioned considerations a total of 11 samples were
collected in the present study, at each sampling site, ha-

An Initial Investigation on the Distribution, Living Conditions and Traits of the Hazel in Great Xing’an Ridge Region 236
zel was collected from a 2.5 m × 2.5 m area. The geo
graphic coordinates of sampling site are listed in Tab le 1
and locations of the study area are showed in Figure 1.
2.2. Test Method
Check out the hazel forest location by GPS and note their
detailed latitude, longitude, altitude and record the habitat
of the hazel forest according to actual situation.
Note the plant diseases and pests on leaves, branches
and shoots of the hazel forest on experimental points.
Compare the types and severity of diseases, pests and
check out which is the most harmful.
Excavate the soil where hazel forest grow and record
the thickness of it.
Have a preliminary understanding of hazel in this area
by investigating the hazel forest, local markets, and in-
formation provided by experts in local forestry bureau.
10 robust Corylus heterophylla trees with no plant dis-
eases or insect pest together with 10 Corylus mandshuria
trees were selected for the experiment. Nuts of the two
Table1. Geographic coordinates of sampling site.
Geographic coordinates
Samling site North latitude East longitude
1 51˚21'32'' 124˚28'14''
2 50˚20'23'' 124˚41'43''
3 50˚33'42'' 125˚75'41''
4 50˚33'21'' 125˚22'12''
5 50˚37'09'' 125˚53'24''
6 50˚56'20'' 126˚04'43''
7 51˚04'30'' 126˚17'54''
8 51˚09'03'' 126˚35'53''
9 51˚09'02'' 126˚08'14''
10 51˚20'17'' 124˚06'12''
11 50˚17'52'' 124˚07'20''
Figure 1. Location of the study area. a: In the image samp-
ling sites are represented by points.
species were selectively picked and brought to the labo-
ratory for air dry. 90 Corylus heterophylla nuts and 90
Corylus mandshuria nuts were randomly selected for the
test and each 30 nuts as duplication 30 days later.
The weight of nuts were weight by 1/10,000 electronic
balance, and fruit size, shell thickness and other related
economic indicat ors we re measured by vernie r calipe r.
The indicators are as follows: traverse diameter (x1),
longitudinal diameter (x2), side diameter (x3), shell thick-
ness (x4), 100-seed weight (x5), plumpness (x6), kernel-
rate (x7) and empty shell rate (x8). And schematic dia-
gram of whole survey procedure is showed in Figure 2.
The experimental data were analyzed by average me-
thod and variance analysis, applying mean square error
test method by spss17.0 statistical softwa re.
3. Result and Discussion
3.1. Distribution of Hazel Forest
The results indicate that there are two hazel species in
Great Xing’an Ridge region and they respectively are
Corylus heterophylla, Cory lu s mandshuria. The mini-
mum altitude that hazel forest distributes was 312 m and
the highest was 461 m. They mainly grow in mountains
or hills from south of Xinlin Town, Huma County, Hei-
longjian Province to south boundary of Great Xing’an
Ridge. Distribution of Corylus Heterophylla was signifi-
cantly wider than that of Corylus Mandshu ria.
Most of Corylus heterophylla grew in the su nny forest
edge or shrub south of the hillside. Corylus heterophy-
lla’s requirements on soil was very high, so zones where
they grew in were fertile, moist, rich in humus and had
deep soil. As a result, much area where hazel forest grew
had changed into farmland, leading to nearly exhausted
resource.
Corylus mandshuri’s requirement on sun was not so
high that most of them grew in shrub north of the hillside
or broad-leaved forest and mixed coniferous forest, and
sometimes mixed with Corylus heterophylla. They pre-
ferred to soil which were moist, rich in humus, slightly
acidic, but tolerates dry, infertile soil. Corylus mandshu-
ria was even found grow in the local limestone rock.
However, due to the high requirements on moisture and
shade, although their distribution was wide, production
turned out to be lower than Corylus h eterophylla.
3.2. Plant Disease and Insect Pest of the Hazel
Forest
Most of hazel forest that distributed in eastern mountains
of Heilongjiang Province was under pure wild state with
no scientific artificial manag ement, resulting in low yield.
Especially for the pest factors, close to 30% - 40% of
hazel suffered from pests each year, causing enormous

An Initial Investigation on the Distribution, Living Conditions and Traits of the Hazel in Great Xing’an Ridge Region237
Figure 2. Schematic diagram for survey procedure.
loss [12].
We checked out the main plant disease and insect pest
harmful to local wild hazel forest during their growth
phase by survey on random samples. The result showed
that the main plant disease was powdery mildew, and
main insect pest were Curculio dieckmani, Zeuzera sp.
Faust Cockchafer, among which Curculio dieckmani
turned to be the most harmful.
As for powdery mildew, diseased branches and leaves
should be removed in time as soon as diseased plants are
found. And for too dens e shrub, cutting down the excess
branches and thinning could help them improve ventila-
tion, light conditio ns, which can enhance the tree’s resis-
tance to disease. In addition, spraying pesticide from
early May to early June is also available for resistance.
As for Faust Cockchafer and the most serious Curcu-
lio dieckmani, we can make use of their suspended ani-
mation and phototaxis of adult pest to capture them arti-
ficially or kill them by black light. What’s more, to pro-
tect and attract a variety of biological natural enemies
can effectively control pests.
3.3. Soil Layer Thickness of Hazel Forest
Corylus heterophylla’s requirement on soil is very high,
so most areas they grow in were fertile, moist sunny hill-
sides which were rich in humus and had deep soil. The
survey showed that th ickness of soil layer where Corylus
heterophylla grew and hadn’t been destroyed proved to
be not less than 50 cm; soil at foot of the mountain s, be-
side the highways and those had even been destroyed by
farmland can still come up to 40 cm thick; and no growth
signs of Corylus heterophylla was found in those areas
thickness of soil layer was less than 30 cm. It indicates
that Corylus heterophylla’s requirement on soil is not
less than 40 cm, so fertile, moist soil rich in humus is
necessary for their growth.
Most of Corylus mandshuri grew in shrub north of the
hillside or broad-leaved forest and mixed co niferous for-
est. Soil which was moist, rich in humus, slightly acidic
was their most suitable survival place. In addition, they
can tolerate dry, infertile soil. Thickness of soil layer
where the hazel forest grew and hadn’t been destroyed
was not less than 45 cm; and most of the soil layer they
grow in ranged from 30 cm to 45 cm. For their strong
ability to endure dry, infertile soil, some were truly found
in the local limestone rock at 51˚20'17''N latitude,
124˚06'12''E longitude.
The requirement of hazel on soil is very high, so fertile
soil and good drainage is indispensable for high yield.
The growth and development will be greatly affected if
bred in the heavy clay or sandy soil which is barren, dry
or stands too much water. In addition, hazel requires 40
cm thick soil and some soil sh ould b e replaced if they are
less than 40 cm [14]. So, our result quantitatively sup-
ports the conclusion that reported by Zhanhui Liu and
other experts, which proved that hazel forest need enough
fertile soil not less than 40 cm for normal growth and for
development in the process of artificial breeding. This
provides a realistic basis for artificial cultivation of hazel
resources and lays a theoretical base for improving their
yield and quality.
3.4. Wild Hazel Resource Utilization
Most of hazel in this area was under the state of natural
growth at this stage with no scientific artificial manage-
ment, combined with destruction from farmland occupa-
tion. As a result, production became very unstable.
What’s more, the strong germination ability of hazel led
to too large density of the wood, so ventilation and light
became insufficient. Consequently, yield and quality was

An Initial Investigation on the Distribution, Living Conditions and Traits of the Hazel in Great Xing’an Ridge Region 238
affected seriously, which confirmed the earlier conclu-
sion reported by Minghua Che and other experts. They
pointed out that the main natural reasons resulting in low
production of hazel were as follows: scarce sunlight for
being distributed under the arbores; poor fruiting ability
due to too old age; intense competition among indivi-
duals because of too large density; arid climate and pest
insect [13].
In addition, as local people’s value cognition of hazel
deepened gradually, greens nuts were always picked by
them, resulting in much reduction. Hazel product deve-
lopment was still in primitive stage. There were no pro-
cessed products, and only primary products were sold on
local market.
Hazel has high economic value. To protect and make
full use of the wild resource can not only improve its
yield and quality, but also safeguard the environment and
ensure the sustainable use of wild resources. Given the
status of local hazelnut resources, artificial rearing and
scientific management are imminent. So, “Artificial and
wild hazelnut garden” is necessary on the base of its na-
tural environment, growth and development law. Only to
guide it to achieve stable, high yield, and thus the for-
mation of industrial-scale, can it meet the economic de-
velopment needs of local area.
3.5. 100-Seed Weight Comparison between
Corylus heterophylla and Corylus
mandshuria
As we can see in Table 2 that 100-seed weight of Cory-
lus heterophylla was more than twice that of Corylus
mandshuria.
3.6. Nut Size and Shell Thickness Comparison
between Corylus heterophylla and Corylus
mandshuria
Traverse diameter, longitudinal diameter, side diameter
and shell thickness of 90 Corylus heterophylla nuts and
90 Corylus mandshuria nuts were respectively measured
by venier calipers and the result is as followed.
As we can see in Figure 3, traverse diameter and lon-
gitudinal diameter of Corylus heterophylla were both
significantly higher than that of Corylus mandshuria,
respectively higher by 33.07% and 25.96%. While side
diameters of both were not so different for Corylus het-
erophylla was only 6.67% higher than Corylus mandshu-
ria in this factor. However, shell thickness of Corylus
heterophylla was p articularly higher than Corylus mand-
shu ria by 83.67%, almost twice of it. The results present
here show that size of wild Corylus heterophylla was
evidently bigger than wild Corylus mandshuria with
clearly thicker shell.
What’s more , each standard devi ation of Corylus hetero-
Table 2. 100-seed weight comparison between Corylus het-
erophylla and Corylus mandshuria.
100-seed weight
variety 1 2 3 4 5 mean
Corylus
mandshuria
(g) 48.34549.21251.561 50.708 47.24449.41
Corylus
heterophylla
(g) 107.131103.853103.679 106.315 104.670105.13
Figure 3. Nut size and shell thickness comparison between
Corylus heterophylla and Corylus mandshuria. The data on
top of the post were the record of the item; below them
were their standard deviation.
phylla nut size was clearly bigger than Corylus mand-
shuria, which indicates both shape and size of wild
Corylus heterophylla were not so homogeneous. How-
ever, Corylus mandshuria showed more stable situation
in these factors and turned out to be very suitable for
commercialization.
3.7. Plumpness, Kernel Rate and Empty Shell
Rate Comparison between Corylus
heterophylla and Corylus mandshuria
Figure 4 showed that plumpness of Corylus mandshuria
was significantly higher than that of Corylus hetero-
phylla by 17.51%. Kernel rate of Corylus mandshuria
was almost twice of Corylus heterophylla. Empty shell
rate of Corylus mandshuria was especially lower than
that of Corylus he terophylla, only 1/4 of it. From Figure
3 we can see that size of Corylus mandshuria was clearly
smaller than Corylus heterophylla. However, the result
present in Figure 4 indicates that Corylus mandshuria
was plumper, had much more kernel and much less em-
pty shell than Corylus heterophylla, which showed great
value of economic commodity.
That Corylus heterophylla was utilized much more

An Initial Investigation on the Distribution, Living Conditions and Traits of the Hazel in Great Xing’an Ridge Region 239
Figure 4. Plumpness, kernel rate and empty shell rate com-
parison between Corylus heterophylla and Corylus mand-
shuria.
than Corylus mandshuria was because of its better eco-
nomic quality traits for it has wide adap tability, large nut
yield, easily preserved pollen, high pollination rate and
fruiting rate, great variation of cross-breeding offspring
and better breeding shape controllability [15]. However,
Figure 4 showed that Corylus mandshuria was plumper,
had much more kernel and much less empty shell than
Corylus heteroph ylla, and what’s more, shell sickness of
it turned to be significantly thinner than Corylus hetero-
phylla, all of which showed great cultivation value and
and economic commodity value.
That yield of Corylus mandshuria was smaller than
Corylus heterop hylla was d ue to its po or distribu tion. So ,
it can be predicted that Corylus mandshuria would create
significant economic value if cultivated artificially in
large-scale.
4. Acknowledgements
Wang Qian, Zhao Di and Liu Wanping would like to
express profound gratitude to advisor for her painstaking
support, encouragement, supervision, and useful sugges-
tions throughout this research. Meanwh ile, we appreciate
the countless support and help so much from Tang
Zhongqiu and Xu Di from Agricultural and Forestry Re-
search Institute of Great Xing’an Ridge.
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