 Item number SCP-628 Object Class, Euclid Special Containment Procedures SCP-628 is contained in Bio-Research Site 104, built on site at the perimeter of its containment is to be clearly marked by a circle of 3-meter wire fence, no less than one kilometer from the edge of the cops. Non-class D personnel are not to enter the perimeter without appropriate hearing protection and seismic sensors. Protective gear sufficient for all personnel on site must be available at all times. All structures on site, and especially the listing post constructed just outside the perimeter fence, must conform to the stringent earthquake and wind-proofing building codes laid out in Document 628-3. Personnel assigned to Site 104 should preferably be selected for a low absolute threshold of hearing. All newly assigned personnel should be briefed on the visual and emotional effects of infrasound. A brief training course on distinguishing these effects from normal human affect is to be made available on site. The weather at Site 104 must be monitored carefully. In the event of a sudden increase in wind speed, the presiding researcher is to be notified. In the event that any winds in excess of 50 kilometers an hour are observed, all personnel are to evacuate to Site 104's soundproofed shelters. Construction may be continued via ground sensors, remote drones, or D-class personnel. Botanical personnel stationed at Site 104 are to monitor SCP-628 and maintain it in good health. Regular consultation with MTF-Theta-4, gardeners, has been scheduled for this purpose. Description Above the soil surface, SCP-628 consists of a copse of 31 large hollow American sycamore Platonus Occidentalis trees, with trunks from 224 to 455 centimeters in external diameter. The copse is a colonial organism. Below ground, the trees are linked by massive hollow woody stolons. These runner trunks, which lie roughly 2 meters below the soil surface, connect the base of each trunk to between 3 and 7 of its neighbors. An average stolon is 2 meters in diameter and completely hollow. Above ground, the trees never produce leaves, flowers, or fruit. Although their bark is photosynthetic in summer, as is typical for P. Occidentalis. The individual trunks are designated SCP-628-1 through 31. All major above ground trunks have at some point been broken off. Their truncated ends serve as openings to the trees' shared internal cavity. Each member of SCP-628 is oriented geographically such that the prevailing winds at the site tend to blow directly across these openings, producing considerable Helmholtz resonance. Observation by remote camera has revealed contractile structures, superficially resembling animal spinkters, located at numerous points inside SCP-628's trunks and branches, each capable of restricting or blocking airflow to a particular large branch. The trunks' internal diameters and wood structures differ enough that each resonance chamber thus created, when sealed off from the others and subjected to sufficient wind, produces a different pitch. On average, each tree has three resonance chambers. The cops can produce 93 notes in total. Its total range is equivalent to that of a pipe organ, although much of it lies in the low base and infrasound. The notes correspond to a western chromatic scale. SCP-628 is capable of isolating any given resonance chamber within 0.2 seconds, quickly enough to play recognizable music. Under sufficiently windy conditions, it does so spontaneously. The cops' repertoire includes numerous works composed for pipe organ between 1366 and 1898, as well as a number of previously unknown compositions. Level 2 personnel and above may refer to Site-104's database for recordings of original works. The sounds produced by SCP-628 are not anomalous beyond their origin. Ordinary infrasound, however, has been shown to cause feelings of fear, awe, sorrow, anxiety, and disorientation. Some waves, at or very near 18 hertz, the resonant frequency of the human eye, can also produce simple optical illusions. Since the sound is only audible under ideal conditions, exposed personnel frequently ascribe supernatural causes to these sensations. Incident 628-023 On 0404, 2000, as part of an approved test overseen by Dr. OG, two D-class personnel equipped with chainsaws attempted to harvest SCP-628-8. Approximately at the moment of contact between the chainsaw blade and the item's bark, the local wind speed began to increase from 9 km an hour to 77 km an hour in less than 80 seconds. SCP-628 activated accordingly, playing at roughly 150 decibels, a piece later identified as an augmented version of J.S. Box, little fugue, in G minor. While it remained active, personnel across Site 104 experienced effective and physical disturbances, consistent with the effects of high decibel infrasound. On-site seismometers recorded the equivalent of a Richter magnitude 0.63 earthquake. Anomalous weather activity persisted for 3 minutes 31 seconds, exactly the duration of the fugue being played. Wind speed and cloud cover quickly returned to normal once the piece concluded. In accordance with containment protocols, experimentation had been suspended shortly after confirmation of anomalous weather activity. SCP-628-8's trunk had been almost halfway severed at that point. When Dr. G in the research team returned to SCP-628-8 five hours later, however, they observed that the damage to the item's trunk had begun to heal. Its bark and wood tissues closed smoothly from both sides of the wound, in a manner inconsistent with known patterns of plant growth. Incident 628-024 On 0504, 2000 events substantially similar to those reported in Incident 628-023 occurred, with a significant difference that SCP-628-8's trunk, which had healed entirely in the intervening hours, was completely severed before evacuation. The item was partially toppled in the wind, before being caught in the branches of its neighbor, SCP-628-15. The damage to SCP-628-8's trunk healed entirely over the following 24 hours, although the item did not write itself in the process. No scar was produced, but data expunged, tension would have considerable interest to the presiding researcher. Dr. G was reprimanded for recklessness.