Strategic Moves: harvesting bamboo shoots in Niiharu

Maintaining bamboo forest is different from the forestry of the other kinds. The bamboo forests require annual thinning. Say, for forests of deciduous broad leaved trees in Yokohama, it is enough to have only once in 10-15 years of thinning / clearing and once in 3-4 years of coppicing for a flat ground. (On steep slopes, the approach differs a bit in order to achieve disaster risk reduction.) Bamboos are far more vigorous. Although their trunks and leaves look very cool with smooth and clean green, they are ferocious in a forest, expanding their “territory” year in and out by spreading rhizome that could destroy the other trees … Hmmmm, maybe bamboos are similar to giant pandas in its spirit … Both look very attractive, but their nature is extremely fierce. And panda eats bamboo leaves … philosophy … !? So as to maintain the overall “peace” of the area, a bamboo forest must be thinned every year at least to stop the “invasion” of bamboos into the neighboring forests. The way bamboos multiply themselves is extremely forceful sprouting. The baby bamboos, aka bamboo shoots, of Phyllostachys pubescens come out almost incessantly during April and May in Niiharu. They poke their head in morning from the ground, and by the evening of the same day the shoots could be 50cm tall. Hence, one of the main activities for Lovers volunteers in Niiharu in spring is thinning bamboo forest by harvesting bamboo shoots. The target: make the forest of “one bamboo per 3m²,” or keep the distance of individual bamboos wide enough for a person to walk with an opened umbrella. Oh, yeah, honestly.

The heads of baby bamboos are
poking out in a forest pass of Niiharu.

Today’s to do:
#4 “Harvesting bamboo shoots of pubescens”
#5 “Maintenance works for bambsoides”

Early April: the first harvest this year!

There are techniques to harvest bamboo shoots. First, the tool. We have a specialized hoe to dig out bamboo shoots with a small blade of about 15cm wide. To hang, literally, of the usage of a bamboo-hoe, we have to wet sufficiently the attachment of a blade on the handle. Simply put, harvesting bamboo shoots is hacking them off from rhizome, which requires (1) impacts, and (2) the power to pull. The blade must be attached to the handle firmly for the job. Otherwise, the best case scenario is a harvester will fall on his/her buttocks with a slipped-out handle. The worst? Call emergency for serious injury. Handle of a bamboo-hoe is made of hard wood that can expand when it absorbs water, so we make it sure the handles suck up enough water before entering the forest.

H₂O over the blades

Second, the objective. (Ah-hem, Yes, I’m talking about the welfare of the broad public.) Bamboo forests in Citizen Forests of Yokohama, majority of them are privately owned, are a part of the tradition for Satoyama life of subsistence agriculture. When volunteers harvest bamboo shoots, it is for land conservation in cultural and environmental sense. Bamboos are healthy for about 5 years in the optimally controlled population, and rapidly deteriorate into dried carcasses of trees. In order to make a bamboo forest healthy and consequently beautiful, we harvest the bamboo shoots … yeah, and we know VERY WELL they are spring delicacy of Japanese cuisine … The objective of our activity is to make individual bamboo tree healthy by making the density of the forest right. Not gluttony. NOT! 

How to prepare bamboo shoots
1. cut off the roots,
but not too much as the part with buds of roots are tasty.

The roots of bamboo shoots are like this.

2. Insert a knife from the bottom,
cut the skin of the shoots, then prise it open.

The edible part is at the core of a shoot,
which has creamy color.

Lots of bamboo skins from one shoot

3. Wash the bamboos, and …

Put them in a large solution of baking soda,
er, about 1tbsp per gallon of H2O?
Telling you the truth, I don’t know ...
I just throw the soda in the pan.
If you have organic rice bran,
you can use it instead of baking soda.
Some say bran works better without rendering
a slightly bitter taste to the shoots.
I doubt it’s about the matter of baking soda.
Niiharu’s bamboo shoots are so soft
and have a taste of cream even with baking soda.

4. Boil until you can insert a skewer smoothly into the shoot.

Prepared bamboo shoots.
Those canned bamboos are at this stage.

And so, third, the identification. When bamboo shoots come out from the ground, only the selected few should be allowed to stand for 5 years. The oldest bamboos are more than 5 years old and have yellowish color. They should be thinned during winter before bamboo shoot harvesting. The healthiest shoots will come out from the rhizome of a tree of about 3 years old. So, to begin with, we identify the place where the best shoots could spout, i.e. near 3 years old trees. Do you remember when we harvested a bamboo for soup cups last winter, my volunteering senior told us the younger the tree, whiter the section. So, (not) to harvest shoots, we look for a tree whose trunk and leaves are still in fresh green, but the sections are not white. Once we find such a tree, look down and walk the ground around it. Baby bamboos have points on their head that will eventually be the crown leaves of the tree. We seek if their crown is coming out from the ground either by sight, or by a touch of our sole. Seeking the shoots by touching is a technique professionals do (and done-well so that the shoots can be eaten row, like famous dishes in 3-star restaurants in Kyoto). We amateurs use our eyes to identify possible shoots. When we find one, we examine the way how it looks. If the shoot comes from the best rhizome, its top is somehow open with yellow-tinge. We must keep it on the ground to be a healthy bamboo tree later. When a rhizome is too young, the top is very green and closely shut. Let’s harvest it. And when a shoot comes from an older rhizome, the top is too wide-open with brownish colors. This one too to be taken.

1 is from too young rhizome, and 3 is from too old.
2 is about right.

This one comes from an older rhizome.

My senior volunteers taught me bamboos do not get fatter. A healthy, fat bamboo begins its life as a healthy, fat bamboo shoot. How tall it becomes is also pre-programmed. When we peel skins from a shoot, we can count the number of skins it had by counting the rings which are the marks of the attachment of skins. A grown-up bamboo has exactly the same number of sections with the number of tiers of the skin. Healthy, fat bamboo shoot will become a healthy, fat bamboo tree with robustly long sections each whose number is equal to the layers of skins covering the shoot. The shoots from too young or old rhizome are thin and have fewer rings when they are skinned. They will not be a beautiful bamboo tree, and hence to be harvested.  We also have to keep in mind possible density of the forest when we choose a shoot. For example, when the space is too congested, we have to assess leaving a shoot is OK even if it is vigorous.

When we peel bamboos one by one,
the rings come out.

Bamboo shoots really come out a lot after a rainy day.
Consider density …

Fourth, the digging. As you can see in above photos for cooking, the top part of a shoot is mainly skins that are not edible. Even when a crown comes out of the ground, the majority of the eatable part is underground. So, with the special hoe we dig the ground around a shoot. The first rule of digging for bamboo shoots is, never burrow the soil over the crown of a shoot. If you do that, there is a high probability you damage the shoot. Instead, remove the soil in front of a bamboo shoot by positioning ourselves always properly. The second rule is, know the anatomy of bamboo shoots. If you study the crown of a shoot carefully, you notice the tips are aligned and often curved down to one direction. They are looking the same way as the rhizome underneath goes. Our task is to hack-off the shoot from the rhizome. When we get rid of the enough soil along the line of a rhizome, the job will be done. i.e. We do not have to unearth 360^o equally around a shoot. The third rule is, dig deep. Gourmands know the exquisite texture at the bottom of bamboo shoots, immediately above the roots attached to a rhizome. So, we have to keep hoeing until we reach to the rhizome.

After a bit of digging around the crown

Could you figure out a rhizome there?

Fifth, the harvesting and clean-up. Once you reach to a rhizome, position yourself 90^o against the rhizome, and strike the bottom of the shoot with your hoe. The best is an insertion of the blade from the direction the tip inclines. When you hit properly, the blade bites the shoots, and you pull and prise off the shoot from the rhizome. We must be careful here. Unless you plan to stop the spread of the rhizome at the point, the rhizome should be left alive especially if it is a young one for the next year to shoot. After harvesting the bamboo shoot, the hole we created must be filled by the dirt we removed, for the forest to keep on going healthily.

A second before the impact

Gotcha!

Cleaning up

… Easier said than done. To begin with, choosing which shoot to take requires very strategic thinking of long term with uncertainty. “This bamboo has white sections, meaning, it’s last year’s. Then, the shoot next to the tree is supposed to be too young to preserve, but the spacing from the parent is ideal. Should I take it or not? If I take it, will the space be filled next year with a better shoot?” Harvesting bamboo shoots is continuous decision making of this kind, which could be overwhelming sometimes. And, digging. The Bamboo shoots are like icebergs. The crown we can find is really a tip. Say, if we can find a 5cm high crown, probably the beneath is like 30cm or more. My senior volunteers remove very quickly the soil around the bamboo to the rhizome. I could not. Their 5 minutes work was like 15 minutes’ toil for me. The inclination of the ground would also make the digging difficult. Well-cared bamboo forests in Niiharu have very thick leaf mold that nurtures the soft and tasty bamboo shoots. But when we have to stand firm to excavate, cushy sloped ground does not help for a novice.  Striking the bottom was another trouble. Unless I hit with enough force, the blade could not sink its teeth into the shoot. In addition, hitting the right point needs a practice, even if not aiming for 300 hitter like Ichiro.  Swishing a long hoe with a heavy blade many times is … futile. Moreover, the ideal direction of the impact could be blocked by a beautiful adult bamboo or another shoot. Positioning to a better strike demands brainpower after hard mining. As one of the tasks volunteers do is keeping the forest pass safe, poking bamboo shoots are to be “removed” from the road. But … popular roads in Niiharu are really compacted and very difficult to dig. Digging deep the hard soil with tons of sweat, but the games are disappointingly small … oh, so sorry bamboo shoots that could not be fatter, surrounded by a straightjacket … and my arms ache…

Which one to dig!?

A shoot from rich leaf mold

In a forest pass, not only the crown of a shoot,
but also a rhizome became bare due to compaction.
Sad.

Shoots coming out to the road … too small …

Still, tons of bamboo shoots!

Whatever my aching back, this year, bamboo shoots have kept coming during April and well-into May. According to the veteran volunteers, there of course is yearly difference. Maybe, this year we have a bumper crop of bamboo shoots. Every weekend after forestry activity, it becomes a kind of duty for volunteers to carry 5-10k of bamboo shoots home. Yeah, if you buy them in supermarkets, it costs around 800 yen per small shoot. Niiharu’s bamboo shoots are very soft and milky compared with supermarkets’. Is it because they are so fresh when we boil it? It’s really a perk for being a forest volunteer in Yokohama … up to a point. Distributing expensive veggies among neighbors weekly is not strategically wise for local politics. Inevitably, a large quantity of shoots remains home. Following the advice of senior Lovers of Niiharu, my family has freezed some shredded shoots (“good for veggie sushi after stewing them with soy source, but not so tasty for pilaf as fresh shoots, you know”), and been busy processing them by thinly slicing and drying for storage (“We can enjoy free bamboo shoots year-round!”). And yet, for more than a month, bamboo shoots occupy the menu of our family meal … Yeah, they are rich in a variety of vitamins and minerals, and only 30kcal for 100g with zero cholesterol. But, 100g of boiled bamboo contains, according to 2015 Standard Tables of Food Composition in Japan (by Ministry of Education, Culture, Sports, Science and Technology), 

• Protein 3.5g
• Fat 0.2g
• Carbohydrate 5.5g
• Mineral 0.9g
• Saturated fatty acid 0.04g
• Unsaturated fatty acid 0.09g
• Dietary fiber 3.3g
• Water 89.9g

i.e. Lots of fibers. Last week, I experienced indigestion, and till then I was proud of myself with strong stomach … Lots of free bamboo shoots require strategic meal plan, seriously.

Bamboo shoot pilaf

Stewed bamboo shoots
and stair-fried leaf mustard (another spring delicacy in Japan)
with sausages

Bamboo-shoots’ season is wisteria time in Niiharu.

If you find a problem in the Niiharu Forest, please make a contact with

Office for the Park Greeneries in the North 北部公園緑地事務所

Yokohama Municipal Government Creative Environment Policy Bureau 横浜市環境創造局

Phone: 045-311-2016 (I guess in Japanese only)

FAX: 045-316-8420 (I hope there is somebody who can read English …)

Niiharu Administrative Office / Satoyama Exchange Center 新治管理事務所・里山交流センター

Phone: 045-931-4947

Fax: 045-937-0898

Email: info@niiharu.jp

http://www.niiharu.jp/

Sit Thee down upon This Flowery Bed … while it lasts, mate

Spring! During April, I’ve joined once-a-week activity of Lovers of Niiharu. Every weekend morning, the same route, but the different scenery. First the pale pinks and whites of cherry blossoms over there, then the forest became pale green, a bit brighter green, bright pink of peaches, brilliant yellow of kerria japonicas … the burst of colors everywhere! The air is clean and Niiharu changes its hues every weekend. Spring has come!

So, it’s fit to have a volunteer training class this time of the year in Niiharu. In the middle of April, the city of Yokohama held the annual spring one-day training class for registered volunteers. The title, “30 Spring Flowers in the Forests of Yokohama, for beginners.” (In this post, the photos of flowers with “#” are in the list.) The instructor was Ms. Yoshiko Kitagawa, a former botanist for University of Tokyo, who was born in Yokohama and knew the ecology of Niiharu inside-out. Ms. Kitagawa was assisted by another botanist, Ms. Ookuma, who is studying Niiharu since 1990. The ladies were like veteran spring fairies who were so familiar with Niiharu Forest. Ms. Kitagawa was one of the members who drafted the Yokohama Citizen Forestry Guideline and Conservation /Management Plan 横浜市森づくりガイドラインと保全管理計画.

A crab is also living in Niiharu.
Could you see, it’s in the middle, under the log?

The structure of the class was similar to that for the birds in February. First, in Okutsu House, we had a lecture about ecology of forests in Yokohama, then Ms. Kitagawa introduced us how to “read” the feature of plants to identify each with forms of flowers, leaves, etc. After this quick “plant observation 101” (and lunch), we went into Niiharu Forest to learn the actual plants in situ. About 3 hours of walk for plants, and then we returned to Okutsu House to review our observation. I didn’t know the difference between monoplane and compound leaf, and the usefulness to know such anatomy of plants to distinguish them in the wild. … I’m a so ignorant city rat …

Calanthe Discolor, near threatened species,
at the gate of Okutsu House in April.
Of course, it’s not wild.

Ms. Kitagawa said last year she surveyed 20 ha ag lands in Tochigi Prefecture, and found 450 kinds of plants. In contrast, about 2,000 m² of Asahi Yato in Niiharu has at least 300 varieties. This is something. Though, the situation is still critical … According to Ms Kitagawa, reviewing scientific records since the mid 19^th century we know Yokohama has had 2,052 kinds of plants. As of 2001, 594 of them are extinct / near-extinct, and 677 are alien, and quite often invasive, species. Take dandelion. Niiharu has 3 kinds of dandelions. One is native Kanto dandelions. Another is white dandelions which are a cousin of Kanto dandelions brought in at the middle of the last century by a bride who came from Kyushu for one of the landlords (; Kyushu’s native dandelion is white … I’m praying for Kumamoto now). The third one is ferociously invasive European dandelions which are expanding their territory at the expense of natives. The reason is simple. Kanto dandelions are easygoing local bunch, which flower only once in spring. They need another plant to produce seeds that require spending a hot summer of Japan dormant and sprout in autumn. In contrast, vigorous Europeans found Japanese climate warmer than their native land, and comfortable to flower continuously for more than 6 months. In addition, they do not need another plant to bear effective seeds that sprout immediately after they find a soil to settle. Before babies of Kanto dandelions begin their life, the game is over. The land is taken by the Europeans. Yokohama is an international port city, often a first gate of entry. Similar stories are happening for the other species, Ms. Kitagawa said.

In Niiharu.
Kanto dandelions (taraxacum platycarpum; #6)
whose involucre is curling in.

In Niiharu.
European dandelions (taraxacum officinale)
whose involucre is warping outside.

In Niiharu. White dandelions (taraxacum albidum).

I first thought it may be a regular xenophobic thing in Japan. But Ms. Kitagawa’s logic made sense to me. She said these days when she went to the other Asian countries, especially hotter places like Indian Subcontinent, ASEAN cities, or mega-cities in southern China, she found the vegetation is becoming more and more uniform. The biodiversity is decreasing region-wide. Japan could take the same route if we let aliens occupy the land. Those countries in the north, like the UK, had originally small biodiversity so that warmer climate makes them able to host “exotic” fauna and flora, AND their biodiversity increases at least numerically. They can say their land is open for “foreigners.” Japan is different. It’s an archipelago with a unique and very diverse local ecology. If we allow our environment to be identical to the “world standard,” maybe Shanghai?, the math for the biodiversity of the earth yields smaller number of fauna and flora in the entire planet. It is a loss, and so Japan is in color red at the site of Conservation International. More protection efforts required.

A colony of Delphinium anthriscifolium in Niiharu.
It was first introduced from China to Koishikawa Botanical Garden
of Tokyo University in the 19^th century.
 It escaped from the “cage,”
and is now spreading around Tokyo,
expelling locals like Corydalis incisa.

In Niiharu. Corydalis incisa (#27).

I didn’t know the current common garden variety of lilies, roses, and hydrangeas world-wide have ancestors taken from Satoyama in Kanagawa Prefecture in the 19^th century. Ms. Kitagawa and Ms. Ookuma told us the wild specimens of them were shipped from the port of Yokohama to make the root of the gorgeous roses in Victorian gardens, the stems more robust for lilies decorating cathedrals in France, and the hydrangeas in New York. Ms. Ookuma is doing fixed-point observations every 5 years in Niiharu. The latest one was just last year, and she found many places once her team could study are now roads, often asphalted where Euphorbia helioscopia are profusely sprouting from the edge. They are coming from somewhere outside of the island. Where are the original residents now? Hmmmmm.

Euphorbia helioscopia at the edge of Niiharu Forest.
Well, certainly,
the road is easy to walk now thanks to the paving …

In Niiharu.
Lilium auratum, prefectural flower for Kanagawa,
and Polygonatum odoratum (angular Solomon’s seal, #2).

When Satoyama was a field for subsistence rice agriculture, the ecology of Niiharu was sustained by regular maintenance jobs by farmers. The roads criss-crossed Yato-da rice paddies were hand-mowed max 5 times from April to October so that the height of the typical plants was short, like Mazus miquelii. Though, it was the place only farmers used. The soil was not compacted … Now, nostalgic city dwellers walk the road heavily, which makes the soil difficult for the plants to sprout … Before, the community had a tacit consent to cut trees and grass on slopes surrounding Yato-da paddies without the consent of the landlords. Normally, this job was done twice a year before rice planting in late spring and rice harvesting early fall, in order to make the space for the planting and harvesting tasks. It let the area around the Yato-da paddies forest edge with lots of sunshine and air circulation where varieties of plants, tall and short, thrived.

Could you figure out the difference
in the height of grasses on the banks of the paddies,
and slopes surrounding Asahi-yato?

In Niiharu.
Lxeris japonica (#5) and Mazus miquelii (#28).

This farmland was before Yato-da rice paddies.
The landlords found it difficult to maintain and
reclaimed the place for vegetable farming.
However, the structure of surrounding slope remains.
My seniors of Lovers told me they did heavy mowing
and thinning of Sasaella ramose and
overgrown Zelkova Serrata there more than 10 years ago.
The scenery is recovering from the neglect
to the memory of Yato-da slope.

In Niiharu.
Euphorbia sieboldiana (#18)
on the slope around Yato-da paddies.

I recalled the description in Niiharu Conservation and Management Plan about the surrounding area of Asahi-yato before 2009. It said the slopes had tall grasses due to the neglect. According to Ms Kitagawa, certainly dormant seeds can sprout with enough sunshine. But their ability has a limit. When the seeds are kept underground, the rate of germination is 70% after 10 years, 50% for 20 years, and drops to 20% after 30 years of abandonment. Here comes the motivation to draft the Yokohama Citizen Forestry Guideline and Conservation / Management Plan. It seems to me, Ms. Kitagawa chose to compromise the ideal Satoyama maintenance of 24/7 work with the practical volunteer-based conservation strategy of about 1-2 times a week activities by urbanites. She said the how-to part of the Guideline and Plan is written for maximizing the benefit of once a week volunteering for the urgent need of Satoyama ecology. If we consider 2010 was the year when the Guideline and Plan became full-swing in Yokohama, 1980 was the last year when the neglected but possibly resuscitated seeds on the ground were buried. For Niiharu, JR Tohkaichiba station opened in April 1979, which was the time demand for residential developments reached Niiharu Forest from Tokyo. If we think Niiharu in the historic perspective, Yokohama Green Up Plan was a kind of close call to protect the last stand of the nature in Yokohama … I’m now listening interesting stories about this from my senior volunteers and people who volunteer in another Citizen Forests. I’ll report it to you later. J

In Niiharu.
This coppiced Quercus acutissima is ready
for choosing the most vigorous sucker.

In Niiharu. Female of Helwingia japonica (#21).

In Niiharu. Male of Helwingia japonica (#21).

Here is the list of 30 Spring Flowers for the class. We could find all of them in Niiharu of one April afternoon. They are indicator species we volunteers should watch … phew!

#1 Viola phalacrocarpa

#2 Polygonatum odoratum (angular Solomon’s seal)

#3 Polystichum polyblepharum

#4 Lonicera gracilipes var. glabru

#5 Lxeris japonica

#7 Potentilla fragarioides var. major

#8 Lycoris sanguinea

#9 Stachyurus praecox

#10 Ajuga decumbens

#11 Ranunculus cantoniensis

#12 Rubus hirsutus

#13 Chaenomeles japonica                          

#14 Cymbidium goeringii

#15 Viola grypoceras

#16 Viola verecunda A. Gray

#17 Valeriana flaccidissima

#18 Euphorbia sieboldiana

#19 Anemone flaccida

#20 Cirsium japonicum

#21 Helwingia japonica

#22 Disporum sessile

#23 Lithospermum zollingeri

#24 Viola phalacrocarpa

#25 Staphylea bumalda  DC.

#26 Polygonatum lasianthum

#27 Corydalis incisa

#28 Mazus miquelii

#29 Rubus palmatus var. coptophyllus

#30 Arachniodes standishii

In Niiharu.
The forest of Cryptomeria japonica where
many Arachniodes standishii (#30) thrive underneath.
However, the ridge of this area is right next to
the Kirigaoka residential area,
and the forest edge has been heavily mowed
to accommodate the request of the residents.
It created a corridor of winds into the forest
which could affect the moisture level in the valley.
Winds would harm the ecology suitable for ferns.
We must be vigilant for the situation.

By the way, Anemone flaccida (#19)
have come out a lot in the place where
we mowed Sasaella ramose last fall
during the Forest Volunteering 101. Yayyyyyy!

If you find a problem in the Niiharu Forest, please make a contact with

Office for the Park Greeneries in the North 北部公園緑地事務所

Yokohama Municipal Government Creative Environment Policy Bureau 横浜市環境創造局

Phone: 045-311-2016 (I guess in Japanese only)

FAX: 045-316-8420 (I hope there is somebody who can read English …)

Niiharu Administrative Office / Satoyama Exchange Center 新治管理事務所・里山交流センター

Phone: 045-931-4947

Fax: 045-937-0898

Email: info@niiharu.jp

http://www.niiharu.jp/