After years of efforts, agricultural researchers have in recent years brought back to north China plain oak trees that had long disappeared.
“电影《冰河世纪》看过吧，那只松鼠苦苦追寻的‘美食’，就是栎树的果实。栎树还有一个诗意的名字，叫橡树……”6月14日，在前往河北雄安新区的途中，许中旗教授就像打开了话匣子，全程都在给同行人员普及着栎树知识。
"Have you ever seen the movie of Ice Age? The 'favorite food' that the squirrel is painstakingly looking for is the fruit of Oak tree. Oak also has a poetic name 'Xiang Shu' in Chinese…"said Prof. Xu Zhongqi, vice-president of the Hebei Agricultural University, who has done a lot of research into the rare tree species and brought oak trees back to the Hebei Plain.
许中旗是河北农业大学林学院副院长。他研究发现，人类大规模出现前，雄安新区所在的河北平原曾经密布着以栎树为主的森林，后来随着人口日益增多，农业发展规模越来越大，把原始森林植被破坏了，栎树才从平原地区消失。多年来，许中旗执着于把栎树“请”回河北平原，而雄安集团生态建设公司技术总监徐成立也恰好有着同样的追求。
Xu said that before humans appeared en masse, the Hebei Plain, where the Xiong'an New Area is situated, used to be densely covered by forests, mainly oak trees. With the expansion of the human population and agricultural production, the pristine forest vegetation was destroyed, and oak trees gradually disappeared from the plain.
盛夏的“千年秀林”郁郁葱葱，在雄安新区10万亩苗景兼用林建设项目第4标段，被“请”回这里的栎树树干已经有成人的拳头粗。“看，咱们这片栎林长得不错吧！”刚见到许中旗，徐成立就“炫耀”起这片在“千年秀林”重现生机的栎林。
“‘千年秀林’的树种选择要和千年之城的雄安新区相匹配，需要具备乡土、长寿、美观、珍贵、抗逆等特点。这些栎类全部具备，所以我们才把栎类作为‘千年秀林’的树种之一。”为了让这个古老的乡土树种回归，徐成立、许中旗和国内外专家做了大量严谨细致的调查研究。
"The selection of tree species for the beautiful forest must be well matched with Xiong'an. They must possess such traits as indigeneity, long life, good looks, preciousness and adversity resistance. The oak family trees have all these traits. That is why we have made oak one of the main species in the forest," said Chief Technology Officer Xu Chengli of the Ecology Restoration and Rehabilitation Company under the Xiong'an Group.
6月14日，雄安集团生态建设公司技术总监徐成立正在查看“千年秀林”里栎树幼苗的生长情况。长城网·冀云客户端记者 信贺宁 摄
On June 14, 2022, Xu Chengli was checking the growth of oak saplings. (Photo by Xin Hening/Great Wall New Media)
2018年4月，他们和德国专家一起从雄安新区出发，按栎树可能分布的地域向西追溯，来到纬度相近的保定易县深山区。几经寻找，终于在一座庙宇旁发现了大片的天然栎树林，为栎树在雄安新区“安家”提供了有力佐证。
In April, 2018, Xu Zhongqi and Xu Chengli together with German experts set off from the Xiong'an New Area on a tour of tracing places where there might be distribution of oak trees. They came down deep in a mountain area in the Yixian County of Baoding city, which has similar latitude. They searched and in the end found a large expanse of natural oak forest, thus providing evidence to the idea that oak can make the Xiong'an New Area its home.
“易县山区漫山遍野的栎树，与我们常见的灌木状栎树丛长势截然不同，就像舒婷诗歌《致橡树》中描绘的那样，‘铜枝铁干，像刀，像剑，也像戟’，一棵棵矗立在山坡上，美得像一幅幅画。”许中旗感叹说，“它们在山野间恣意生长的模样，正是‘千年秀林’追求的最佳状态。”
The oak trees that are growing all over the mountainous area in Yixian County are totally different from the common bush type of oak. "They have bronze branches and iron trunks, like knives, like swords, like halberds, too" as is described by Shu Ting in her poem "To the Oak Tree". They are standing aloft on the mountain slopes, looking as beautiful as a painting, Xu Zhongqi acclaimed, adding that their unbridled growth in the wild is the best state of the forestation project pursues.
6月14日，雄安集团生态建设公司技术总监徐成立（左）和河北农业大学林学院副院长许中旗行走在“千年秀林”中，仔细观察栎树生长情况。长城网·冀云客户端记者 郑佳洵 摄
On June 14, 2022, Xu Chengli (left) and Xu Zhongqi were walking and observing the growth of oak trees. (Photo by Zheng Jiaxun/Great Wall New Media)
这次寻访，让栎树穿越千年重回河北平原的梦想照进现实。此后经过连续4年的精心试种，如今在雄安新区“千年秀林”，已经形成了3个较大规模、以栎树为主体的同心圆状林片，中间是栎树，外圈混交五角枫、栾树、国槐等，再往外仍种植栎树，模拟林木在大自然中的存活状态，使“千年秀林”更加贴近自然森林。
The oak tracing tour has made the dream of returning oak trees to the Hebei Plain a reality. Then, after four years' trial planting, the Xiong'an New Area's forest has formed a shape of a concentric circles, with oak trees in the center surrounded by mixed forests made up of maple trees, goldenrain trees and Chinese scholartrees. In the future, more oak trees will be planted in the outer circles, modelling on the state of natural forest, making the beautiful forest as closer to a natural forest as possible.
近自然育林需要坚持的首要原则，就是选择乡土树种或至少是适应立地条件的引进树种。“栎树、黄连木等优质树种，历史上就分布在华北平原，它在这个地方暂时消失了，不代表它现在不能在这个地方生长，这里就是它们的家。”徐成立肯定地告诉许中旗，“试种结果证明，我们当时的选择完全正确。”
The prime principle of making a forest as natural as possible is to choose indigenous species or at least species that are adaptable to local conditions. Such high-quality trees like oak and pistacia lentiscus used to be distributed on the Hebei Plain. Their disappearance is temporary. It doesn't mean they could not grow again in the place that used to be their home. Xu Chengli told Xu Zhongqi confidently that "the trial planting has proved that their early choice is absolutely correct."
生长在易县深山中的大片成熟栎林，茂密粗壮、冠大荫浓。长城网·冀云客户端记者 信贺宁 摄
The mature oak trees deep in the mountains of Yixian County are growing exuberantly with big crowns. (Photo by Xin Hening/Great Wall New Media)
“这片栎林长势很好，我希望它能够更加茁壮成长，成为我们在平原地区推广栎林的一个样板。”许中旗和徐成立再次约定，要通过进一步研究，让“回家”的栎树尽快适应家乡环境，重新把森林植被构建起来。
"The oak forest grows very well. I hope that it grows better so that it will become a model for popularizing oak on our plain area," said Xu Zhongqi. The two "Xu's" have made another appointment of making further research so as to make the returned oak adapt to the local conditions and restore and rehabilitate the forest vegetation as soon as possible.
“我们培育的森林不仅要接近自然，更要优于自然，这样的林子才是最稳定、最绿色、最有潜力、最可以实现生生不息的。”徐成立自豪地说，过去5年时间里，雄安新区已累计造林45.4万亩、2300多万株，森林覆盖率由最初的11%提高到32%，为地球增添了一抹亮眼的“雄安绿”。
"The forest we have planted and cultivated is not only close to but also better than nature, as such forest is the stablest, the greenest, promising the most potentials of realizing continuous reproduction in an endless succession," Xu Chengli said proudly. Over the past five years, the Xiong'an New Area has afforested 30,266 hectares, with 23 million trees. The forest cover has been raised from 11 percent at the beginning to 32 percent, adding more greens to the earth.
Editor：Zheng Bai
