秋分那幾天，晝夜等長在曆法上只是一個瞬間，島上的動植物把它攤成兩三個星期。恆春半島的天空會出現一年裡最密集的猛禽隊伍，北海岸和太魯閣的岩壁冒出先開花、花謝了才長葉的球根，行道樹的黃花一邊落，一邊結出玫瑰紅色的果。
同一段時間裡，三千公尺的草坡進入花季尾聲，新竹一塊濕地裡的一年生食蟲草開始結種，台東縱谷的河床上有一種紅果快要熟。地點分得很開，時間全壓在同一個半個月。
天上：九月下旬的過境高峰
赤腹鷹的主要過境期落在九月中旬到九月底。墾丁國家公園從 1989 年開始做秋季過境猛禽調查，每年 9 月 1 日到 10 月 31 日，在社頂自然公園的凌霄亭這類制高點上一隻一隻數。2025 年那次，主要過境期是 9 月 12 日到 9 月 30 日，赤腹鷹計得 404,122 隻，超過近十年平均 196,811 隻的兩倍；中間 9 月 22、23 兩天還因為颱風停止調查。
赤腹鷹走完換灰面鵟鷹，時間在十月上旬到中旬，2025 年記到 104,721 隻。牠們夜棲在滿州鄉附近的山區，午後到五點左右會在里德橋一帶盤旋集結、俯衝停落，當地叫「落鷹」。
岩壁：花葉不相見
金花石蒜開在秋分之後那一個月。金山獅頭山公園一帶是九月底到十月底，太魯閣峽谷則是十月前後，直接長在大理岩的峭壁上，當地叫它峽谷之花、國慶花。石蒜屬的球根花謝了才長葉，花和葉一輩子碰不到面；日本人把同屬的紅花石蒜叫彼岸花，秋分前後三天正是他們的秋彼岸。馬祖的紅花石蒜早一點，九月初開到九月底。
金花石蒜在 2017 年的臺灣維管束植物紅皮書名錄裡列為國家瀕危。早年因為外銷切花被大量採挖，野外族群一路變少，金山從 2008 年開始復育，種回九千三百株。
街上：一棵樹一年換好幾種顏色
臺灣欒樹是台灣特有種，全島中低海拔 0 到 1,200 公尺都有，花期八到十月、果期十到十二月。秋分前後常常在同一棵樹上看到黃花還在開、蒴果已經轉成玫瑰紅；果實是囊狀的，成熟後三瓣裂開。這幾年荔枝椿象和褐根病的壓力不小，林業及自然保育署建議暫時不要大量栽植。
高山、濕地、河床
高山當藥是特有種，長在中部到南部 2,000 到 3,500 公尺的開闊草生地或向陽林緣，八到十月開淡黃色的小花，紅皮書列為國家易危。塔塔加一帶的觀察紀錄顯示，高山植物開花的高峰在七、八月，九月開始減少，結實的種類數反而在九月達到最高——秋分在高山上是花季收尾、果季開場。
長葉茅膏菜是一年生的食蟲植物，大約三月萌芽、五月開花，十月左右結束整個生長季。台灣本島比較穩定的野外族群在新竹竹北的蓮花寺濕地，紅皮書同樣列為國家瀕危。那塊濕地位在軍事管制區內，不對外開放，只有核准的志工能定期進去除草、採種，隔年春天再播回去，族群才留得住。
臺灣火刺木也是特有種，分布在花蓮立霧溪到台東市之間的縱谷平原，海拔 500 公尺以下，三到五月開花、八到十一月結果。1980 年代盆栽熱潮時整片被挖走，河床又年年疏濬，野外幾乎不見。老一輩的人管那些紅果叫「小蘋果」，小孩牛綁好就往河床衝。花蓮林區管理處在花蓮溪高灘地的月眉橋到米棧橋之間，留了大約五公頃做復育。
要去看的話
這幾件事的時間差很開，行程得照日子排。赤腹鷹九月中到月底，灰面鵟鷹十月中，金花石蒜九月底到十月底，火刺木的紅果十月。想看滿山白芒得再等，白背芒十一月到十二月才盛開，九月底上山會撲空。蓮花寺濕地不對外開放，想看食蟲植物只能循荒野保護協會的志工管道。
這份清單上有六種植物、兩種鷹。2017 年的紅皮書名錄清點過，臺灣有野生紀錄的維管束植物是 5,188 個分類群，其中 4,442 個進了評估流程，27 種已經確定不在了。照這樣一種一種認下去，一輩子也認不完。會寫下來，是因為認得的人多一個，被留下來的機會就多一點。季節會繼續換下去，我也就繼續往下列吧。
— 溫以君
Two Weeks Around the Equinox: Six Plants and Two Migrating Hawks
On paper, the autumn equinox is a single instant when day and night split evenly. On the ground, the island stretches that instant into two or three weeks. Over the peninsula at Taiwan’s southern tip, the sky fills with the year’s densest procession of migrating raptors. On the cliffs of the north coast and in the marble gorge on the east coast, bulbs push up flowers before any leaf appears. Street trees drop yellow blossoms on one side while ripening rose-red seed pods on the other.
In the same stretch of weeks, alpine grasslands above 3,000 meters wind down their bloom, a wetland in Hsinchu watches an annual carnivorous plant set seed, and a riverbed in the Taitung valley carries a red fruit toward ripeness. The places are scattered. The timing is not — all of it compresses into the same half month.
In the Sky: The Late-September Peak
The Chinese sparrowhawk (Accipiter soloensis) passes through mostly from mid to late September. Kenting National Park has run an autumn raptor survey since 1989, counting birds every year from September 1 to October 31 from vantage points like Lingxiao Pavilion in Sheding Nature Park. In 2025, the main passage ran September 12–30, with 404,122 birds counted — more than double the ten-year average of 196,811. The count paused on September 22–23 when a typhoon hit.
After the sparrowhawks comes the grey-faced buzzard (Butastur indicus), passing in early to mid October; 2025 recorded 104,721 birds. They roost overnight in the hills near Manzhou Township and, in late afternoon, circle and stoop down into the area around Lide Bridge — a local phenomenon known as “falling hawks.”
On the Cliffs: Flower and Leaf Never Meet
Golden spider lily (Lycoris aurea) blooms in the month following the equinox — late September to late October around Jinshan’s Shitoushan Park on the north coast, and around October in Taroko Gorge, growing straight out of marble rock faces where locals call it the “flower of the gorge.” Lilies in this genus flower only after the leaves have died back, so bloom and foliage never overlap in the same season. Japan calls a related species, the red spider lily, higanbana, since it flowers around the autumn equinox. Matsu’s red spider lily — the county flower there — blooms slightly earlier, early to late September.
Golden spider lily is listed as Nationally Endangered in Taiwan’s 2017 Red List of Vascular Plants. Decades of over-harvesting for the cut-flower export trade thinned wild populations; Jinshan has been replanting since 2008, restoring roughly 9,300 plants.
On the Street: One Tree, Several Colors at Once
Taiwan golden rain tree (Koelreuteria henryi), endemic to the island, grows from sea level to 1,200 meters across lowland and mid-elevation areas. It flowers August–October and fruits October–December. Around the equinox a single tree often shows yellow blossoms still open alongside pods that have already turned rose-red; the bladder-like pods split into three sections at maturity. Pest pressure from lychee stink bugs and root disease in recent years has led forestry authorities to advise against large-scale new planting.
Highlands, Wetland, Riverbed
Swertia tozanensis, endemic and listed as Nationally Vulnerable, grows in open grassland and sunlit forest edges between 2,000 and 3,500 meters in central and southern Taiwan, flowering August–October in pale yellow. Observations around the Tataka area show alpine plants peaking in bloom during July–August, tapering by September — while the number of species in fruit peaks in September. At altitude, the equinox marks the end of flowering season and the start of fruiting season.
Drosera indica, an annual carnivorous plant, sprouts around March, flowers in May, and ends its growing season around October. The most stable wild population on Taiwan’s main island survives in the Lianhuasi Wetland in Hsinchu’s Zhubei — also listed Nationally Endangered. The wetland sits inside a military restricted zone, closed to the public; only approved volunteers enter periodically to weed, collect seed, and resow it the following spring to keep the population going.
Taiwan firethorn (Pyracantha koidzumii), also endemic, grows below 500 meters along the valley plain between the Liwu River near Taroko and Taitung City, flowering March–May and fruiting August–November. A potted-plant craze in the 1980s stripped wild stands, and annual riverbed dredging finished the job — it’s nearly gone from the wild now. Older generations called the red fruit “little apples,” a snack for kids who’d tie up the family cattle and run down to the riverbed to pick them. Hualien’s forest district office now maintains about 5 hectares of restoration planting on the floodplain between Yuemei Bridge and Micang Bridge.
Timing a Visit
These events don’t overlap neatly, so a trip has to be scheduled around dates. Chinese sparrowhawks: mid-to-late September. Grey-faced buzzards: mid-October. Golden spider lily: late September to late October. Firethorn fruit: October. Anyone hoping for silver grass fields should wait — that bloom peaks November–December, and a late-September hike will miss it entirely. The Lianhuasi Wetland stays closed to the public; seeing the carnivorous plant means going through an approved conservation volunteer channel.
Six plants, two hawks, one list. Taiwan’s 2017 Red List counted 5,188 taxa of vascular plants with wild records on the island; 4,442 went through full assessment, and 27 have been confirmed extinct. Working through a list like that one species at a time could take a lifetime and still not finish it. Writing it down is worth doing anyway — one more person who can recognize a plant is one more chance it gets to stay. The seasons keep turning, and I will keep working my way down the list.
— Wen Yi-chun
延伸閱讀
https://justfly.idv.tw/s/X21mhbV