Epilogue: After urbanization and endangered Asarum tamaense Makino

 

Stachyurus praecox in Tama Hill

In 1931, Dr. Tomitaro Makino (; my post on October 27, 2023) named a species of Asarum (; my post on May 6, 2022) found in Kawasaki. It is called Asarum tamaense Makino. As it is in the genus of evergreen Asarum, it loves humid forests with leaves sprout out straight from the ground and flowers with brownish calyx stick to the soil. Asarum can move VERY slowly from the place parent plants locate. Estimated speed of its movement is about 1 or a couple of kilometers per 10 thousand years. i.e., it has time to evolve adjusting to a particular environment where the “original” established (literary) its roots. Actually, Japan has 50 known independent species of Asarum each of which is exclusive to a very limited geographical area, similar to Darwin finches in Galapagos. In 2020, a team of botanists led by Dr. Yudai Okuyama of National Museum of Nature and Science published in Annals of Botany their findings from DNA sequencing for almost all (mainly) Japanese Asarum. They theorized when Japanese archipelago was a part of Eurasian Continent 7 to 10 million years ago, the ancestors of these local Asarum moved from a part of now-China, and diversified their DNA pattern suitable for each distinctive environment where they stay for a very long run. Environments of Japanese humid forest floor can be different even between the neighboring small valleys, and hence we have many species of Japanese Asarum. Asarum contributes to a high biodiversity of Japanese nature.

Asarum tamaense Makino
 in a forest of Kanagawa Prefecture.
I won‘t tell you where I found them.

For the case of Asarum tamaense Makino, it has adjusted the climate of suburban Edo (aka Tokyo) whose soil is fluvial strata created by Tama and Tsurumi Rivers + volcanic ash from Mt. Fuji. DNA-wise it is locally very unique species spreading on the eastern edge of Fossa Magna region. Asarum tamaense was once ubiquitous in Tama Hills and little bit of Sayama Hills. Oh, by the way, it was the area where a massive housing development occurred during the 1960s and the 1970s. Please guess what happened to Asarum tamaense. Nowadays it’s a rare occasion finding Asarum tamaense in local neighbourhoods. Many survived Asarum are in college campuses where professional botanists roam, or in town where the landlords close the access to their land ... Moreover, as Asarum genus loves humid forest floor, drying ground accelerates the demise of their species. For example, if you leave ordinary forest on Tama Hills without proper management, sasa bamboos cover the floor completely. The spread of sasa roots over the surface of ground obstructs rainwater to seep in. Asarum tamaense will die for thirst. Now, Asarum tamaense Makino is nationally designated Endangered Species.

Once
people become not caring about forest floor in Tama Hills,
Sasa bamboos dominate.

The story of Asarum tamaense Makino is related to the issues surrounding Yokohama‘s Citizen Forest, don‘t you think? Normally, they flower in April, but in this boiling climate it might be earlier this year ...

Flowers of Japanese raspberry
which flower the same time as Asarum tamaense Makino.
I took the photo in Tama Hills.

If you have any questions about Yokohama’s Green Tax and Green Up Plan, please make a contact with

Strategic Planning Division, Green Environment Bureau, City of Yokohama
横浜市みどり環境局戦略企画課

Phone: 045-671-2712
FAX: 045-550-4093 

Email: mk-kikaku@city.yokohama.lg.jp

Friends of Friends: Lovers Associations for Yokohama’s Citizen Forest

 

In a sense, the strategic designation of Urbanization Control Area and Lovers Association System are two sides of a coin for Yokohama’s environmental protection. First, the city secures green spaces from rampant urbanization pressure. Then, the policy introduces the forestry and “gardening” by Lovers Association to stop the preserved forests degrading into a damping ground for social nuisance. When the city gave preferential tax treatments for landlords allowing their property to be Control Area, the office put the condition in the contract for the title holders to form or collaborate with “citizen volunteers group” who engage in forest management. As a carrot, the city pays a Lovers Association based on the length of strolling path within the Citizen Forest, where the Lovers are expected to keep it safe for visitors enjoying the forest. By becoming the leader of a Lovers Association, the landlord shares this subsidy with the other members of the Lovers, and says “thank you” to the volunteers maintaining his/her property.

So, the majority of Yokohama’s Citizen Forest has Lovers Association which was formed by landlords, their relatives, and/or old acquaintances. It’s not anomaly for these groups to limit the membership. In this regard, Niiharu is one of the exceptions as the Lovers Association does not have any condition to be a member. Here is the latest list of Yokohama’s Forest Lovers Associations which allows anybody who can join the volunteering. The number of the groups in the catalogue are far smaller than the number of citizen forests and smaller forests registered at the city for environmental protection. Why are many Lovers closed community? The reason is obvious. The land is a private property. Yes, the landlord agreed to open his “garden” to the public for strolling. But yielding saws and sickles within his/her assets is a different matter ... It is already 50 years since the Citizen Forest System was inaugurated. The system has worked well. Yokohama has become a city with green spaces here and there. Yes, landlords are grumbling, but they also have preferential tax treatment and subsidy for maintenance of their estate. In the end it’s not so bad deal, is it?

Unfortunately, the scheme may be approaching a critical point. The culprit is rapid aging of society. Imagine, you landlord is now an octogenarian. You are the leader of a Lovers Association for your forest. The member of your team is long-time friends of yours. You guys have had a good time enjoying large-scale gardening in your asset. And the average age of your team is … octogenarian. Maybe you have kids. They are Hamakko, proud city slickers. They also are not young, maybe in their 40s or 50s, the prime age as working force for Japanese economy, i.e. busy. Yes, they know their dad has not so small land in Yokohama. They will inherit it. But

(1) they are not interested in dirt works of forest management, and/or

(2) they do not want to manage their dad’s human relation in Lovers Association. 

They plan to pay inheritance tax, period. No thank you for continuing dad’s pal-circle. The closed nature of Lovers Association guaranteed a certain level of forestry output, but it has now led to a serious problem of generational change and the resulted labor shortage. Lots of Lovers Association for Citizen Forests face currently the problem of continuation, i.e. sustainable existence.

The city office is in damage control mode. For example, take Jike Citizen Forest (; my post on October 7, 2015) which is, maybe, a property of proud descendants of Samurai with family tradition of at least 900 years. Unfortunately, the forest now does not have a team of Lovers who takes care of the maintenance of ancestral land. It could mean some inheritance incidents would have occurred lately and heirs may have paid their inheritance tax with land ... I don’t know exactly what happened. But one thing is for sure: the City of Yokohama hires professional landscapers to clear the undergrowth along the strolling paths in Jike Forest, which is normally done by Lovers Associations. The office also organizes a couple of “fun forestry day for anybody who can come to the Jike forest” in a year. Is it enough? … Yokohama is in the climate zone for temperate rain forest. The maintenance requires more than a couple of days per year for the forest to be at least comfortable to walk, let alone preserving biodiversity. Jike’s forest is rapidly becoming dark due to overgrowing trees and bushes. Comparing, say, nearby Kurokawa Forest (; my post on December 15, 2024) on the edge of TamaHills, the difference is now apparent. I doubt if the Jike forest maintains variety of living creatures which just a couple of years ago welcomed us in a nicely maintained forest …

Commercial rice cultivation is continued in Jike community.

Though, the forest circling the rice paddies is …

Pro-landscapers mechanically mow the grass
to 1m inside the forest from the path.
Er, OK, good job.

It’s not a unique example. Shomyoji Temple Citizen Forest (; my post on December 4, 2015) does not have Lovers Association either. Masakarigafuchi Citizen Forest (; my post on August 21, 2015) is lucky. When its Lovers Association was seriously preparing for closure, a group of young neighbors happened to visit the forest. They were interested in the forestry work and the retiring guys and the City persuaded them to “inherit” the management of Masakarigafuchi Forest. Not all the forests in Yokohama are so fortunate …

And so, the conclusion comes to the word of “Coordination Saves the World” again. Tokyo was once engulfed with enthusiasm for bulldozers. Now it has only large parks. Yokohama has managed to keep neighborhood greenery in urban environments so far. But we are in the middle of rapid demographic change. In this new world, closed associations cannot achieve even status quo. To sustain our success, we need cooperation of neighbors, especially new and young people next door who have potential to pass the baton for the next 50 years and beyond. The problem is how to find such people. The saving grace is these days kids in Yokohama are taught SDGs in schools and know, at least in textbooks, the importance of sustainable greenery that can lead to poverty reduction and coordination for world peace. Let us see how we can go from here …

If you have any questions about Yokohama’s Green Tax and Green Up Plan, please make a contact with

Strategic Planning Division, Green Environment Bureau, City of Yokohama
横浜市みどり環境局戦略企画課

Phone: 045-671-2712
FAX: 045-550-4093
Email: mk-kikaku@city.yokohama.lg.jp

Checkmate: Games of Chess and Yokohama’s Citizen Forest

 

Take Niiharu Citizen Forest. It‘s the largest Citizen Forest of Yokohama. The landlord who had the biggest acreage was Mr. Okutsu who unfortunately died in 2000 just before the inauguration of the Citizen Forest (; my post June 24, 2016). He did not have a person who could inherit his property or negotiate with the city what to do with the title of the land. Upon his death the land he owned became municipal property. The remaining landlords of large or else are still counted about 90 people for Niiharu. Do you think they easily agreed to aggregate their land for becoming urbanization control area? We Japanese were/are not so good people. Niiharu is not an exception. It’s a typical land-ownership pattern for Yokohama’s Citizen Forests, large and small. Under this constraint at the time of forming citizen forest network, the city’s planners must have worked strategically to make the forest “Citizen Forest” with the designation of Urbanization Control Area. They fully utilized small meshes covering the entire city.

Lots of landlords for Niiharu

Imagine you had a land, maybe 10m*10m?, within a certain mass of greenery of Yokohama. The next to your forest had another landlord. Actually your land was surrounded by several neighbours who owned ecologically similar forest of small patches. Now, one of the neighbours agreed to make his/her land Urbanization Control Area. Another neighbour decided to sell the property to the City, Prefecture, or even to the National Government. Maybe, the person or the heir used their property for tax purposes. (Well, Niiharu Citizen Forest has several small areas of national land. In a sense, Niiharu Forest has National Park within it.) They were tiny, but eventually, say in 10 or 20 years’ time, your land could be encircled by Urbanization Control Area. One day, you noticed you did not have access to your land unless you passed the Urbanization Control Area. You had insisted to keep your land OK for urbanization at least legally. But you did not have legitimate way anymore to bring bulldozers for constructing “urban“ place on your land. Moreover, did you think easy to connect your property with electricity, water and sewage system of the city? You had to run around many offices for permit etc. Finally, even if you planned to sell your 10m*10m land for a housing developer, did you think there was a buyer for such land?

This part of Niiharu is owned by
the mixture of private and municipal landlords.

For officials who plan to preserve green spaces within the city, that‘s the strategy exploiting the small meshes over the area. Lots of landlords with the equal property right means the diverse idea of land management for each mesh. Within about 100 landlords for 70ha, which is Niiharu‘s case, there is no single policy agreed to manage the greenery. That‘s the point of start. For an official who aims to expand the protected area, the first task is to find title holders who sympathize the environmental protection. The reasons why they think so could be different, but they all agree importance of preserving the ecology of the land. That’s more than enough. Such landlord could be persuaded to make the acreage Urbanization Control Area. If one corner of a land obtained the title, and the landlord started enjoying preferential tax treatment and/or almost free help for land management including weekend forestry by Lovers Society, their neighbour may begin to think the option of making their property also under the Control Area. The next job of the city officer is to find or nudge the neighbours into such direction. Little by little, the property of “against Control Area” would be checkmated. It has been a long, patient, and often unsung or even disliked duty for the city officers in order for keeping the city green. But they were/are very clever. They played chess games, or Go games, for a long haul. They have succeeded. Look. Now in 2025, Yokohama has 47 Citizen Forests and numerous smaller green spaces here and there.

Viola keiskei Miq in Niiharu,
preserved thanks to Urbanization Control Area designation.

The strategy game does not end with the demarcation for Urban Control Area. Yes, once awarded the title of “Urban Control Area,” removing the label requires long legal procedure that often does not match with the benefit from urbanization of the land. (In the end, it’s the system defined by national law passed and modified by National Diet.) Still, for landlords to enjoy the advantage offered by the municipal government, it is based on contract with the city. For example, basically every 10 years landlords for properties within a Citizen Forest have chance to revise and renew their contract with the city. Before, maybe, the title holders lived near the forest. During these 50 or so years, many original members passed away and their relatives inherit the property. The passing of legal title has done with preferential tax treatment for Urbanization Control Area … And now, not every heir lives near, or even in, Yokohama. Some of them may have established their own household in, say, the USA. To maintain Citizen Forest, the city officers must negotiate every landlord, for Niiharu’s case 90 of them, wherever they are on the planet to reach an agreement for the next 10 years’ land-usage. The discussion can take for years. Do you think it’s easy? The most difficult task for local civil servants in charge of Yokohama’s greenery is to get hold of the time-limited agreement with these various landlords.

That’s the way how Yokohama secures green spaces within the city, different from Tokyo. But it’s not all. Aside from the periodical revision of land contracts, the city must think about how to keep environmentally secured land free from nuisance or even crime. Under our climate of temperate rain forest whose dominant vegetation is evergreen broad-leaved trees, leaving the greenery without human intervention must make the forest very untidy and dark. The existence of such space in a crowded city of 4 million people invites crime next door. Besides, dark and untidy forest surely has lower biodiversity which is a perverted result for environmental management with Urbanization Control Area. Here comes the system of Lovers Association. I will tell you about it next week. 😉

This part of Niiharu was a veggie field around 1945
when the entire nation was starved due to the War.
80 years later, Lovers engage in regular maintenance
to make the forest floor bright,
which is important for the vegetation to sprout.

If you have any questions about Yokohama’s Green Tax and Green Up Plan, please make a contact with

Strategic Planning Division, Green Environment Bureau, City of Yokohama
横浜市みどり環境局戦略企画課

Phone: 045-671-2712
FAX: 045-550-4093 

Email: mk-kikaku@city.yokohama.lg.jp

Promising Start: Nagatsuda-shuku Citizen Forest 長津田宿市民の森

The City of Yokohama opens one new Citizen Forest per year these days. Admitting its size is getting smaller, I think it is something we try to preserve our greenery in the megalopolis Tokyo. Fiscal 2020 is the turn for Nagatsuda-shuku Citizen Forest that 長津田宿市民の森 is near JR/Tokyu Nagatsuda Station JR/東急 長津田駅. It opened to the public on April 1^st, this year. Let’s have a look of the place.

The access to the forest is easy. Please leave Nagatsuda Station from its south exit. When we come out, on our right is an office building for JA Yokohama. Please pass in front of it, and turn right at its corner. It’s an alley way running along the tracks of JR and Tokyu. Walking for 5 minutes or so along the busy train services, our road becomes a slope. Please keep going until you find a “peak” in front of you, and another slope on your left, at the corner of Konpirajinja Yasaka Shrine 金毘羅神社八坂神社. Whichever slope you take, we can reach to the Forest, but today let’s take the left one that is going to the back entrance to Nagatsuda Elementary 長津田小学校. In 20m or so, the slope reaches to its peak (and the entrance to Nagatsuda Elementary). On your right is a small unpaved trekking road which runs along the school building. Please take this one, and soon you’ll see the signpost saying ”Nagatsuda-shuku Citizen Forest.”

The south exit of Nagatsuda Station

Please take this road shown by the arrow.
 Oh, this branch of JA Yokohama does
 a small farmers’ market from 14:00
 every Tuesday and Friday.
 Young farmers of the area bring their fresh produce
 for a reasonable price.

The road turning at the corner of JA is like this.
 Adelante, por favor.

We can see the “peak” over there.

Let’s take the left road.
 Could you see red painting over there?
 It’s the back entrance to Nagatsuda Elementary.
 The forest on our right is for the Shrine.

At the Elementary, there is this signpost
 showing us the direction to the Forest.

This road eventually becomes like this …

to here,
 the entrance to Nagatsuda-shuku Citizen Forest.

The structure of the strolling route for the 3 ha Forest is damned simple (; map, here). There is the central road going from the southwest to the north east of the Forest. The northeastern exit is where we’ve reached from Nagatsuda Station. There are 3 short sideways that allow us to experience inside of the Forest. As for the main road for Tsunashima Citizen Forest (; my post on June 26, 2015), it seems to me, the central road running the Forest is a commuter road that is a shortcut to Nagatsuda Station. So, lots of locals are coming and going through the forest. The central road is a ridge way and the Citizen Forest mainly expands to the north slope of a hill. Area-wise, roughly, bottom 1/2 of the hill is off-limit for casual visitors since it is designated as a nature conservation area.

The main way

We can easily recognize
 where the sideways go from the center road.
 The Forest has these picnic benches.

Off-limit areas are fenced.

It’s easy to walk Nagatsuda-shuku Citizen Forest. We go the main road and take sideways as we like. All the sideways are visible from the arterial now, because the mowing and thinning were done just recently. It’s easy to spot small plants here and there on the forest floor. The Forest is a baby as a Citizen Forest, and so the management of the place is still at the beginning. I think the place has a potential to show us the type of ecosystem typical for Tama Hills, eventually. Roughly 4/5 of Nagatsuda Forest is facing to the north. Possible natural ecosystem here could be for north-facing slope of Tama Hills 多摩丘陵. Mr. Hideshige Uchino 内野秀重, the director of Nagaike Park for Hachioji City 八王子市立長池公園, Tokyo, once told us north-facing slope with natural vegetation these days is not so common for Tama Hills due to heavy housing development. We may find natural characteristics for north-facing hillside of Tama Hills in Nagatsuda-shuku Forest in few years.

On a new stump,
 there came lots of wood ears (Auricularia auricula-judae).

The Forest had a small colony of Tricyrtis hirta.
 Please treat them carefully …

Tama Hills lie on a sort of ecological border between northern and southern Japanese vegetation. The strikingly clear-cut frontier is the approach to Yakuo-in Temple of Mt. Takao 高尾山薬王院 (; my post on December 22, 2017) where northwest slope consists of deciduous broadleaved trees and southeast is for evergreen broadleaved trees. Warm air from the Pacific Ocean and chilly winds from Siberia hit the bumps of Tama Hills and create a mosaic of wood zones. Not only trees, but also forest floors can show this complexity, especially in the forests of northern Tama Hills. Secretly known unique ecosystem for north-facing slope of Tama Hills is in my beloved Niiharu Citizen Forest 新治市民の森. Although it’s not so striking as for Mt. Takao, north-facing slopes of Niiharu tend to have plants that incline to colder soil, such as western bracken fern (Pteridium aquilinum). Nagatsuda-shuku Forest can also be a good exhibit of Tama Hills, I expect, because of its direction.

Pretty flowers of Oplismenus undulatifolius

Their Agrimonia Pilosa var. japónica is large.

When you leave from the Forest, you can take the left road which is paved, that will lead us to the small peak we saw when we came from Nagatsuda Station. This route goes through a small community that I guess was for landlords of Nagatsuda-shuku Forest. Beyond the rail tracks, we can see rolling hills of housings typical for Tokyo’s suburbia. Before, the area was of forests and grassland suitable for exercise of Japanese Imperial Army. In the shrine we passed to enter the Forest, there is a large monument commemorating Crown Prince Hirohito 裕仁 (Emperor Showa 昭和天皇) observed almost a century ago a massive drill. The reason why the forest has a name with “Shuku 宿” is, the community spreading south of the Forest was a post town for Oyama Street 大山街道, once popular among pilgrims from Edo (Tokyo) to Mt. Oyama 大山 (; my post on March 17, 2017). Actually, Nagatsuda area has several historical remnants typical for Japanese villages near the capital city Edo. If you live near there, you can explore the memory of village-suburbia life of Japan centuries ago. Here is a walking map you may be interested. These days such “Exploring Our Neighbor” walk is uber popular in Yokohama. Reason? COVID-19, of course. It may be safer in open air than in crowded shopping center, isn’t it?

The left road is going down.
 The forest on our right is also a part of
 Nagatsuda-shuku Citizen Forest,
 but it is off-limit for visitors.

Some trees in the closed area of the Citizen Forest are
 observable from the road.
 This is a pretty Euonymus hamiltonianus Wall.

I’ve found a large colony of
 Juniper haircap moss (Polytrichum juniperinum)!

The monument commemorating the Crown Prince.

Hmmmmmmm … typical suburbia …

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
FAX: 045-316-8420

If you find environmental issues in Kanagawa Prefecture, please make a contact with Kanagawa Natural Environment Conservation Center 神奈川県自然環境保全センター
657 Nanasawa, Atsugi City, 243-0121
〒243－0121　厚木市七沢657
Phone: 046-248-0323

You can send an enquiry to them by clicking the bottom line of their homepage at http://www.pref.kanagawa.jp/div/1644/

Magical forest of ferns: Kamikawai Citizen Forest 上川井市民の森

Probably with a very bureaucratic reason these days, the City of Yokohama opens one Citizen Forest 市民の森 per year. 2018 is the turn for Kamikawai Citizen Forest 上川井市民の森, opened on 1 April 2018. As of July 2018, no official internet description is available for this forest. But, it’s not a forest freshly designated within a sea of houses. Actually, it’s a sort of a gap area of 10.1 ha between Seya Citizen Forest (19.1 ha) 瀬谷市民の森 and Oiwake Citizen Forest (32.9 ha) 追分市民の森. For some time, the forest was left as a closed “grey area” within the North Forest of Yokohama’s Citizen Forests. I guess there were long negotiations between the landlords and the city for what to do with this place surrounded by 2 large citizen forests, the venerable Hodogaya Country Club 程ヶ谷カントリークラブ, and Seya Prefectural High School 神奈川県立瀬谷高校 … Anyway, now the place is opened as a Citizen Forest of Yokohama, and so, the continuation of the North Forests of Yokohama is complete, from Seya Citizen Forest to Niiharu Citizen Forest 新治市民の森 via Yokohama Zoorasia. That’s something we should celebrate for environmental improvement, I think. Moreover, the Forest itself is, I tell you, magical!

Kamikawai Citizen Forest
 is there at the tip of a larger yellow arrow,
 next to the Hospital.

The access to Kamikawai Citizen Forest is the same for Seya, Oiwake, and Yasashi Citizen Forests 矢指市民の森. The nearest public transportation facility is Seibu Byoin-mae Bus Stop 西部病院前 for Sotetsu Bus #116 or Kanachu Bus #Sakai-21 (time table, here), from Sotetsu Mitsukyo Station 相鉄三ツ境駅. From the Stop to the entrance of the Forest, it’s about 100m: you’ve got the idea, haven’t you? You can spend ¥210 for one-way of the bus, or actually it’s just 1.3km from Mitsukyo Station. Although the route is slightly going up, walking is not that hard. When you walk from Mitsukyo Station, the road is lined with large cherry blossom trees; i.e. in spring it must be gorgeous. On your left we can see Tanzawa Mountains 丹沢山系 over there. In any case, first go to Yokohama City Seibu Hospital of St. Mariana Univ. School of Medicine 聖マリアンナ医科大学横浜西部病院, and the entrance to the Kamikawai Forest is (almost) on the other side of the road in front of the parking for the Hospital. Easy. Oh by the way, there is no toilet or potable water in Kamikawai or Seya Forests. Please complete whatever you need before you enter the Forests. 😉

The ticket gate of Mitsukyo Station.
 After exiting the gate, please immediately turn left.
 Then,

we cross an overpass above the bus terminal including
 for the service to the Hospital and beyond.
 Adelante, por favor,
 and go down the steps of the flyover.

In front of you at the foot of the stairs is this map
 showing us the route to the North Forests of Yokohama.

We can just follow the direction of the above map.
 On our way,
 there is this sign vouching for us the right direction.

The tree-lined route goes through a residential area ...

And brings us to the crossing with
 the 4-laned Nakahara Street 中原街道.
 Just keep going straight.

The road from the crossing to the north is
 somehow loved by local drivers.
 If we drive there,
 we can enjoy a ride within “calm forests.”
 Bonus: it is a shortcut to Route 246 and
 Yokohama-Machida IC of Tomei Express Way

And we soon meet Yokohama Seibu Hospital on our right.
 The photo was taken from the bus stop for services from Mitsukyo Station.
 It’s the core hospital for people living in the north-west of Yokohama.
 Corollary: when you have to come here, it’s serious.

In front of the Hospital Parking is this three-forked road
 with the traffic light named “Entrance to Seya High School”
  瀬谷高校入口.
 The entrance to Kamikawai Citizen Forest is
 at the tip of the arrow in this photo.

Here it is. 😄

Now the Kamikawai Forest is officially a member of Citizen Forests family, the combined area of Seya, Oiwake, Yasashi, and Kamikawai Forests is 67.2ha, same as the Niiharu Citizen Forest (; an info from a member for the Lovers of Niiharu, i.e., me; Niiharu would become larger this fiscal year). The newly-added forest is about 15% of the area, not so big. In addition, as it’s next to the Seya Forest, the differences in elevation between the points of 5 trekking roads for Kamikawai Forest are definitely smaller than in the other Citizen Forests. Walking here is not hard. Having said that, the Forest is a part of the sources for Izumi River 和泉川, a tributary of Sakai River 境川 pouring to Sagami Bay 相模湾 in Katase Beach 片瀬海岸 (which is the beach in front of Enoshima Island 江の島, and the place of a legendary Battle of Sexes between the goddesses and a dragon) of the City of Fujisawa 藤沢市. The Forest certainly has slopes that can be slippery. Comparing with the Seya Forest, the place is definitely wetter and so more insects’ bites could be common for visitors during the season. Wearing the standard hiking gear is the MUST. And that’s the reason why Kamikawai Forest is enchanted. It has a magnificent undergrowth of ferns.

4 adjacent forests for Yokohama’s North Forests

A map of Kamikawai Citizen Forest.
 The Forests is the area with “KA” points.
 You see? It has only 5 roads:
 KA1-KA2, KA2-KA3-KA4, KA1-KA4, KA1-KA5, and KA4-KA5.
 When we enter the forest from the entrance
 I’ve shown above, which is KA5,
 we can choose either KA1-KA5 or KA4-KA5 routes.
 This map can be found at KA1 and KA4.

KA2 point. KA1-KA2 is the road
 long-used for Seya Citizen Forest.
 On the right of this photo is Seya Forest.
 On the left is Kamikawai Forest.

So, KA1-KA2,
 or Nosakai-michi 野境みち for Seya Forest,
 has a feel more for the Seya Forest,
 i.e. relatively dry.

Around KA3,
 we cross a small wooden deck over a stream
 that is the source for Izumi River.

See? This part of the forest is wet.

When I’ve been there,
 I met lots of ground prowling insects,
 like Necrophila japonica (Motschulsky),
 or one with a shiny green back.
 (I could not take a photo of it!)
 This is a Carabus insulicola kantoensis Ishikawa et Ujiie,
 commonly found in Kanto area.
 It means the Forest can give them enough animal food to thrive.

Thanks to a long gestation period for opening, the roads within the Forest are still relatively soft. No gnarling roots of trees due to treading are exposed yet. The forest is mainly consisted of afforested cedars with occasional Quercus myrsinifolia, Cornus controversa, etc. all of which are at least 20m high. The next level of trees is familiar Acuba japonica, Trachycarpus fortune, and the other shade trees of so-so height. And the floor. I’ve been there just after a visit of a typhoon and the roads were still wet and the leaves were in fresh greens after showers. The fiesta of ferns and the creepers covered the forest floor with vivid hues of emerald. Polystichum polyblepharum, Stegnogramma pozoi ssp. Mollissima, Arachniodes Standishii … The atmosphere kept the moisture of tropical typhoon. The Forest practically looked like a tropical rainforest with rising mist at the height of my eyes. That was miraculous.

A scene along the route KA4-KA5

Beautiful Polystichum polyblepharum

I was welcomed by lots of mole hills.
 The ground was soft.

From KA4 to KA3, the road goes down.

The road KA2-KA3-KA4 was the most mysterious for me.

At least 4 kinds of ferns here …

KA1-KA5 runs along the motor road.
 Yet it preserves this charm.

I’m not sure how long the Forest could keep such wild freshness once it was opened as Yokohama’s Citizen Forest. The rangers of Yokohama Nature Observation Forest 横浜自然観察の森 in the South Forests of Yokohama are so strict for ways to stroll in the place. (“Don’t touch,” “don’t scratch,” etc.) Yet, after so many school excursions and popularity as a part of the hiking course for Yokohama-Kamakura Alps, the place sometimes has a feel as a “well-organized park.” Niiharu Lovers are worrying the effects of regular treading, since Niiharu becomes so popular these days not only for 3 million citizens of Yokohama, but even among Tokyonites ... The current charm of Kamikawai Forest might be due to its debutant status for the Citizen Forest system of Yokohama. But if it is so, it’s a pity. How can we preserve the softness of trekking routes surrounded by magnificent ferns in Kamikawai Citizen Forest?

If you find a problem in the North Forests of Yokohama, 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

FAX: 045-316-8420